You might have noticed that your terminal git push commands do not work anymore and you are required to provide your credentials again. The weird thing is, your regular Github credential (username/password) are not valid anymore!
What you actually need to do is provide an access token when you are being prompt for a password (obvious, right?).
From here, towards the bottom of the page…
If you have enabled two-factor authentication, you must provide a personal access token instead of entering your password for HTTPS Git.