Restore repos from git-data folder

Hi all,

I’ve migrated from v11 to v14, it all went well until I updated to v14.0.
After that GitLab wouldn’t start up correctly, I’m getting a whoops 502 error message. I can run gitlab-ctl configure and it gives no errors.

Then on another server I’ve created a whole new gitlab installation with the latest v14 version, obviously the whole server is empty because it is a fresh install. What I’m trying to do is I still have the git-data files and a backup file from the old server, so is there a way to copy these over to the new server and restore the data? Or if not, at least any advice on how to troubleshoot why the old server is not starting up?