This is a tricky one to track down as I can’t replicate the error; what the error essentially means is that, when PsychoPy looks up your username on Pavlovia, the value it gets back doesn’t include a GitLab ID, which it needs to log you in.
This won’t fix the problem, but if you open the file C:\Program Files\PsychoPy\lib\site-packages\psychopy\projects\pavlovia.py
in Coder and scroll to line 152, just above you could add this:
assert 'gitlabId' in self.info, (
f"Could not retrieve user info, server returned:\n"
f"{self.info}"
)
Which will give a more informative error message telling you what actually was received from the server.