Converting age in years --> months --> days with NA

Hi all- Trying to convert age in years to months & days, accounting for some 'NA' values in respective columns (age in months only recorded for children < 5 years): The following isn't working for me, for some reason.

##Creating an age in years variable for children whose age in months was recorded (preferred; more precise); 
df_temp<-df_temp %>% 
  mutate(age_years_correct = ifelse(floor(age_months/12)!=age_years,
                                    floor(age_months/12),
                                   age_years))
## Trying to substitute age in years recorded for those without an age_years_correct value. 
df_temp<-df_temp %>% 
  mutate(age_years_correct = ifelse(age_years_correct==NA,
                                    age_years,
                                    age_years_correct))
#age in months for those missing 
is.na(df_temp$age_months)
#GHHelp also not working. 
df_temp<-df_temp %>% 
  mutate(age_months_correct = ifelse(age_months==NA,
                                    age_years*12,
                                    age_months))
#Creating an age in days based on age_months
df_temp$age_days<-df_temp$age_months * (365.25 / 12)