Personal Access Token’s are used to grant access to one of your repos with specific permissions. They have an expiry, so when one expires you need to recreate a new one, details are here.
If you’re trying to push and your token has expired, you’ll see an error like this:
> git push remote: Invalid username or password. fatal: Authentication failed for 'https://github.com/youraccount/yourrepo
The first time accessing a repo requiring authentication is simpler because it will prompt you for your id and password (or token). Once you’ve set one up though, it’s not as obvious how to reset a new token value, since the git cli only gives you the above error, it doesn’t prompt you to enter a new password/token.
To replace your cached credentials, use these steps (from here):
git config --global --unset credential.helper git credential-osxkeychain erase host=github.com protocol=https
Press Return twice on the second step. Close your Terminal, open a new one, then:
git config --global user.name "userid" git config --global user.email email@example.com
From your GitHub account, go to Settings from the top right icon, then Developer Settings, then Personal Access Tokens.
Next time you do a push, use the Personal Access Token value when prompted for your password.