.gitignore for visual studio project is not working

To stop tracking the files in the gitignore file;
Open a command prompt and navigate to the directory that contains your solution file (.sln), then run the following commands (first two commands contains dot at last):

1. Remove all of the items from the Git index (not from the working directory or local repository):

    git rm -r --cached . 

2. Update the Git index according to gitignore:

    git add .

3. Commit changes:

    git commit -am "Remove ignored files"

Then open your Visual Studio and sync your repo.
That seemed to do the trick for me. I found the git commands here.