Rstudio not detecting git

I have git installed on my computer and R studio is already linked to it. I also have a github account and a token. I have been committing and pushing changes to github successfully, however, all of a sudden I get a message that everything is up-to-date. Problem is I have made substantial changes in the last week but when I try to commit, git doesn't detect the changes and push tells me that everything is up-to-date. I understand that I need to commit before I can push.

I don't know if the problem is because a few days ago I lost some files in my xx.Rproj in Rstudio and I downloaded my github xx.Rproj as zip file and installed it in my computer replacing the xx.Rproj that I had in my computer with the one from github.

Now that I added some new files to my xx.Rproj, git does not detect the changes and therefore I can't commit and push to github.

I typed git status on the Terminal and I get this message Your branch is up to date with 'origin/main'. nothing to commit, working tree clean

Question: Is it advisable to create a new repository in github and copy all the files from my old xx.Rproj to the new repository? If that is not advisable, how can I make git detect the new changes on my project? Thanks for any hints.