You'll need to update your saved username and password in the git-credential-osxkeychain helper if you change your password or username on GitHub.

Updating your credentials via Keychain Access

  1. In Finder, search for the Keychain Access app. Spotlight Search bar
  2. In Keychain Access, search for github.com.
  3. Find the "internet password" entry for github.com. GitHub Password Entry in Keychain
  4. Edit or delete the entry accordingly.

Deleting your credentials via the command line

Through the command line, you can use the credential helper directly to erase the keychain entry.

To do this, type the following command:

git credential-osxkeychain erase
host=github.com
protocol=https
[Press Return]

If it's successful, nothing will print out. To test that it works, try and clone a repository from GitHub. If you are prompted for a password, the keychain entry was deleted.

Further reading