Unable to git push, fatal: authentication failed, after username change-CodePudding

The way I publish my GitHub code updates is by working in a separate folder, then copy-pasting the folder in the GitHub folder that I can commit and push. I am working in git CL (GitHub Desktop's lost me some work somehow so I uninstalled it). The issue is I changed my username recently. Now when I try to push it fails. It has trouble with untracked changes too but I think I fixed that. It keeps showing me the old username in error messages, and hints that I don't get/think are relevant:

 ! [rejected]        gh-pages -> gh-pages (non-fast-forward)
error: failed to push some refs to 'https://github.com/old_username/old_username.github.io.git'
hint: Updates were rejected because the tip of your current branch is behind
hint: its remote counterpart. Integrate the remote changes (e.g.
hint: 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.

I tried git config --global user.name new_username

I changed git remote to the one with last week when I had the same issues. That time I ended up pushing just fine.

When I try to /git-credential-manager-core.exe unconfigure to undo past authentication, and try again, the git push fails even after trying to authenticate with my new PAT and username.

CodePudding user response：

You need to change the remote with the new URL of the remote repository after the username change.

git remote set-url origin https://github.com/new_username/repo_name.git

Edit:
However, as the error suggests, the problem is not with the username change. It says all clearly:

the tip of your current branch is behind its remote counterpart

If you need to get the remote change you may pull it with;

git pull <remote-name> <branch-name>

Also you may ignore the remote change and force push you local changes with -f option;

git pull -f <remote-name> <branch-name>

CodePudding user response：

Reinstalling GitHub Desktop (after cleaning up all remnant files) solved this. I then cloned repo again, pasted the changes again, used the same credentials as before (same PAT).

Might've been a GitHub bug.