GitHub will no longer accept passwords when authenticating Git operations and will require the use of strong authentication factors. Yubico also posted about the announcement here, and its 2FA hardware keys are an acceptable solution for GitHub users.
In December, we announced that beginning August 13, 2021, GitHub will no longer accept account passwords when authenticating Git operations and will require the use of strong authentication factors, such as a personal access token, SSH keys (for developers), or an OAuth or GitHub App installation token (for integrators) for all authenticated Git operations on GitHub.com. With the August 13 sunset date behind us, we no longer accept password authentication for Git operations.
Check It Out: GitHub No Longer Accepts Passwords, Use Security Keys Instead