warning: user.email has multiple values error: cannot overwrite multiple values with a single value Use a regexp, --add or --replace-all to change user.email. code example
Example 1: git error: More than one value for the key user.name:
$ sudo git config --global --unset user.name "username"
Example 2: git global username --replace-all
git config --global --replace-all user.name "Your New Name"
git config --global --replace-all user.email "Your new email"
OR
git config --global --unset user.name
git config --global --unset user.email