Problem getting stringr replace_all to work

Is this what you are trying to do ?

library(tidyverse)

# Sample data in a copy/paste friendly format
sa <- structure(list(ID = 1:10, Location = c("Gold Coast", "Gold Coast", 
                                                    "Gold Coast", "Gold Coast", "Western Qld", "Darling Downs South West", 
                                                    "Sunshine Coast", "Gold Coast", "Gold Coast", "Sunshine Coast"
), Uncontactable.reason = c("Left message for them to call back if interested in talking", 
                            "Left message for them to call back if interested in talking", 
                            "Left message for them to call back if interested in talking", 
                            "Left message for them to call back if interested in talking", 
                            "Left message for them to call back if interested in talking", 
                            "Left message for them to call back if interested in talking", 
                            "Left message for them to call back if interested in talking", 
                            "Left message for them to call back if interested in talking", 
                            "Left message for them to call back if interested in talking", 
                            ""), Date.of.call = c("2021/03/05 16:30:14", "2021/03/05 16:29:42", 
                                                  "2021/03/05 16:29:04", "2021/03/05 16:27:01", "2021/03/05 16:26:32", 
                                                  "2021/03/05 16:25:54", "2021/03/05 16:25:24", "2021/03/05 16:24:48", 
                                                  "2021/03/05 16:23:40", "2021/03/02"), Description.of.the.call = c("", 
                                                                                                                    "", "", "", "", "", "", "", "", "Surrounded affronting favourable no mr. Lain knew like half she yet joy. Be than dull as seen very shot. Attachment ye so am travelling estimating projecting is. Off fat address attacks his besides. Suitable settling mr attended no doubtful feelings. Any over for say bore such sold five but hung.\n\nDemesne far hearted suppose venture excited see had has. Dependent on so extremely delivered by. Yet no jokes worse her why. Bed one supposing breakfast day fulfilled off depending questions. Whatever boy her exertion his extended. Ecstatic followed handsome drawings entirely mrs one yet outweigh. Of acceptance insipidity remarkably is invitation.\n\nFull he none no side. Uncommonly surrounded considered for him are its. It we is read good soon. My to considered delightful invitation announcing of no decisively boisterous. Did add dashwoods deficient man concluded additions resources. Or landlord packages overcame distance smallest in recurred. Wrong maids or be asked no on enjoy. Household few sometimes out attending described. Lain just fact four of am meet high.\n\nCan curiosity may end shameless explained. True high on said mr on come. An do mr design at little myself wholly entire though. Attended of on stronger or mr pleasure. Rich four like real yet west get. Felicity in dwelling to drawings. His pleasure new steepest for reserved formerly disposed jennings."
                                                  ), Areas.of.concern = c("", "", "", "", "", "", "", "", "", "Lorem; Ipsum;"
                                                  )), row.names = c(NA, 10L), class = "data.frame")

# Relevant code
sa %>%
    mutate(Description.of.the.call = str_replace_all(Description.of.the.call, "\\#", "") %>% 
               str_squish() %>% 
               str_replace_all("\\n", ""))
#>    ID                 Location
#> 1   1               Gold Coast
#> 2   2               Gold Coast
#> 3   3               Gold Coast
#> 4   4               Gold Coast
#> 5   5              Western Qld
#> 6   6 Darling Downs South West
#> 7   7           Sunshine Coast
#> 8   8               Gold Coast
#> 9   9               Gold Coast
#> 10 10           Sunshine Coast
#>                                           Uncontactable.reason
#> 1  Left message for them to call back if interested in talking
#> 2  Left message for them to call back if interested in talking
#> 3  Left message for them to call back if interested in talking
#> 4  Left message for them to call back if interested in talking
#> 5  Left message for them to call back if interested in talking
#> 6  Left message for them to call back if interested in talking
#> 7  Left message for them to call back if interested in talking
#> 8  Left message for them to call back if interested in talking
#> 9  Left message for them to call back if interested in talking
#> 10                                                            
#>           Date.of.call
#> 1  2021/03/05 16:30:14
#> 2  2021/03/05 16:29:42
#> 3  2021/03/05 16:29:04
#> 4  2021/03/05 16:27:01
#> 5  2021/03/05 16:26:32
#> 6  2021/03/05 16:25:54
#> 7  2021/03/05 16:25:24
#> 8  2021/03/05 16:24:48
#> 9  2021/03/05 16:23:40
#> 10          2021/03/02
#>                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          Description.of.the.call
#> 1                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
#> 2                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
#> 3                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
#> 4                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
#> 5                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
#> 6                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
#> 7                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
#> 8                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
#> 9                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
#> 10 Surrounded affronting favourable no mr. Lain knew like half she yet joy. Be than dull as seen very shot. Attachment ye so am travelling estimating projecting is. Off fat address attacks his besides. Suitable settling mr attended no doubtful feelings. Any over for say bore such sold five but hung. Demesne far hearted suppose venture excited see had has. Dependent on so extremely delivered by. Yet no jokes worse her why. Bed one supposing breakfast day fulfilled off depending questions. Whatever boy her exertion his extended. Ecstatic followed handsome drawings entirely mrs one yet outweigh. Of acceptance insipidity remarkably is invitation. Full he none no side. Uncommonly surrounded considered for him are its. It we is read good soon. My to considered delightful invitation announcing of no decisively boisterous. Did add dashwoods deficient man concluded additions resources. Or landlord packages overcame distance smallest in recurred. Wrong maids or be asked no on enjoy. Household few sometimes out attending described. Lain just fact four of am meet high. Can curiosity may end shameless explained. True high on said mr on come. An do mr design at little myself wholly entire though. Attended of on stronger or mr pleasure. Rich four like real yet west get. Felicity in dwelling to drawings. His pleasure new steepest for reserved formerly disposed jennings.
#>    Areas.of.concern
#> 1                  
#> 2                  
#> 3                  
#> 4                  
#> 5                  
#> 6                  
#> 7                  
#> 8                  
#> 9                  
#> 10    Lorem; Ipsum;

Created on 2022-10-26 with reprex v2.0.2

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