That is why, for instance, Heroku reminds us to ignore such large files
git rm -f db/*.sqlite3
echo '*.sqlite3' > .gitignore
git add .gitignore
git commit -m "ignored sqlite databases"
But, if that still does not work, then you need to remove the file from all commit: I would recommend BFG Repo-cleaner
java -jar bfg.jar --strip-blobs-bigger-than 100M some-big-repo.git
cd some-big-repo.git
git reflog expire --expire=now --all && git gc --prune=now --aggressive
And then git push --force
, which is OK if you are the only one working on that repo.