Recently Github started enforcing either use of tokens for access instead of the real password or not using auth in remote's URL - or both (not sure).
So you have to define a token in your account on github site (settings / developer settings / personal access tokens) and use that instead of your current password on those git repos.
From developer
- if the URL inside Git repositories view / your repo / Remotes / origin used to contain authentication info, you have to remove those and create different remotes with URL copy/pasted from github for that repo. Then it will ask for your username and password (where you give the new token instead of your password). I expect this is most likely the problem you have
- if it remembered credentials you have to clear those out either completely or for the affected git remote either from Settings / General / Security / Secure storage / Contents tab or by going to the Git repositories view / your repo / Remotes / origin - right click on the ones affected and do Clear credentials.