Warning: Error in readOGR: no se pudo encontrar la función "readOGR"

Hi! I am trying to publish my app. In the local server it works correctly but when uploading it to shinyapp.io I get the following error
Warning: Error in readOGR: Could not find function "readOGR"
The layers that I am trying to publish are geojson format and I upload them to the app in the following way on the server:
ANZ_SPN19 <-readOGR ("ANZ_nov2019.geojson"), with a setwd () in the directory.
I already tried in different ways, including adding library (rgdal) the ui and on the server but I can't find any solution.
I hope you can help me.
I leave below the logs records:
2020-08-19T14:47:07.059510+00:00 shinyapps[2685170]: Running on host: f6df2ef12ea3
2020-08-19T14:47:07.065402+00:00 shinyapps[2685170]: Server version: 1.8.4-11
2020-08-19T14:47:07.065415+00:00 shinyapps[2685170]: LANG: es_AR.UTF-8
2020-08-19T14:47:07.065429+00:00 shinyapps[2685170]: R version: 4.0.2
2020-08-19T14:47:07.065443+00:00 shinyapps[2685170]: shiny version: 1.5.0
2020-08-19T14:47:07.065444+00:00 shinyapps[2685170]: httpuv version: 1.5.4
2020-08-19T14:47:07.065527+00:00 shinyapps[2685170]: htmltools version: 0.5.0
2020-08-19T14:47:07.065670+00:00 shinyapps[2685170]: Using pandoc: /opt/connect/ext/pandoc2
2020-08-19T14:47:07.065450+00:00 shinyapps[2685170]: rmarkdown version: (none)
2020-08-19T14:47:07.065460+00:00 shinyapps[2685170]: knitr version: (none)
2020-08-19T14:47:07.065516+00:00 shinyapps[2685170]: jsonlite version: 1.7.0
2020-08-19T14:47:07.065526+00:00 shinyapps[2685170]: RJSONIO version: (none)
2020-08-19T14:47:07.254835+00:00 shinyapps[2685170]: Using jsonlite for JSON processing
2020-08-19T14:47:07.258159+00:00 shinyapps[2685170]:
2020-08-19T14:47:07.258160+00:00 shinyapps[2685170]: Starting R with process ID: '25'
2020-08-19T14:47:07.285552+00:00 shinyapps[2685170]:
2020-08-19T14:47:07.285554+00:00 shinyapps[2685170]: Listening on http://127.0.0.1:40889
2020-08-19T14:47:12.732570+00:00 shinyapps[2685170]:
2020-08-19T14:47:12.732573+00:00 shinyapps[2685170]: Attaching package: ‘shinydashboard’
2020-08-19T14:47:12.732574+00:00 shinyapps[2685170]:
2020-08-19T14:47:12.733350+00:00 shinyapps[2685170]: The following object is masked from ‘package:graphics’:
2020-08-19T14:47:12.733350+00:00 shinyapps[2685170]:
2020-08-19T14:47:12.733351+00:00 shinyapps[2685170]: box
2020-08-19T14:47:12.733351+00:00 shinyapps[2685170]:
2020-08-19T14:47:21.715544+00:00 shinyapps[2685170]: Warning: Error in readOGR: no se pudo encontrar la función "readOGR"
2020-08-19T14:47:21.719286+00:00 shinyapps[2685170]: [No stack trace available]
2020-08-19T14:47:21.719451+00:00 shinyapps[2685170]: Error in readOGR("ANZ_nov2019.geojson") :
2020-08-19T14:47:21.719452+00:00 shinyapps[2685170]: no se pudo encontrar la función "readOGR"