This article explains on how to set up an alternate remote url pointing to a different git account.
Add the username and password of your desired GitHub account
git config user.name mew_username
git config user.email new_email
git config -l
git remote set-url origin https://your_username@github.com/your_username/yourproject.git
List the configuration to display all the available accounts
git config -l
credential.helper=osxkeychain
user.name=Other Username
user.email=50510199+otherusername@users.noreply.github.com
core.autocrlf=input
filter.lfs.clean=git-lfs clean -- %f
filter.lfs.smudge=git-lfs smudge -- %f
filter.lfs.process=git-lfs filter-process
filter.lfs.required=true
core.repositoryformatversion=0
core.filemode=true
core.bare=false
core.logallrefupdates=true
core.ignorecase=true
core.precomposeunicode=true
user.name=new_username
user.email=new_username@email.com
Add a remote url with the new username
git remote set-url origin https://new_username@github.com/new_username/projectname.git
Now its safe too push to the remote repository
git push origin master