I was able to fix and then replicate this error by deleting my pavlovia gitlab repo and creating it again. Then when I invite members who had already created a pavlovia account they were able to successfully accept the invite to membership.
If I invited a member who was not already a pavlovia account holder when they click
Accept Invitation, and then register, it then breaks my
Members page on my pavlovia gitlab repo and the member is no longer able to click
Accept Invite (they get a 'Page Not Found` message).
I believe this has something to do orphaned member invites per this issue
@JensBoelte they suggest some commands run in gitlab-rails – do you know if gitlab-rails command line is something Pavlovia gitlab users are able to do? Or is that something our uni’s Pavlovia admin would have to do?