We have no idea.
We need some idea of what your data looks like and what you are doing.
At best, we probably need to see what data you are using>
A handy way to supply sample data is to use the dput() function. See ?dput. If you have a very large data set then something like head(dput(myfile), 100) will likely supply enough data for us to work with. Just copy and paste the dput() output here between
# Before check the correct column names of df
names(correct_con )
correct_con %>% rename(startdate = `start_date / Injury Date`) # remember use `` if a column have a spaces.
I'm just guessing, but if you has a dataframe with a variable called "startdate" that you wanted to rename to "start_date / Injury Date", this is how could do that: