Ok, I had to lose 50 points, but I got the sequence of commands. My sha was correct, but I was doing the tag slightly differently. I did it as per the solution:
git tag -a v1.2.0 -m "Creating v1.2.0 tag."
I basically wasin't annotating with -a and using -m. Not sure why this should fail though. This course is a little bit flaky due to its reliance on interacting with Github. Unlike other courses it doesn't give you hints when you do something wrong.
moderator: Nicely done, and thanks for posting! You do need the
-a, as per the videos (and solutions) but the
-m won't matter. The checking code isn't looking for the comment, but the tag does need to be annotated.