GitHub made changes recently to stop using some generic domains that meant that the dummy email address I was using for commits (to keep my actual email address private) was no longer correct to have contributions counted.
The help at GitHub told me to use the this https://help.github.com/articles/changing-author-info on lmy local clone to change the author info for previous commits, which I duly did in the Git Bash... which went through the rewrite, and informed me that `Ref 'refs/heads/master' was rewritten.
What now? Do I commit/push? There are no changes showing in the repository and the Github repo hasnt changed....
Force push was the answer so, as indicated by @MohammadAbuShady