Repository size double overnight

Size of repository doubled (an got blocked for excess size).

About three days ago, the repository was about 5.4 GB. Then yesterday, it was blocked since the limit of 10 GB was exceeded.

In the last days, I requested to export the repository but I never got the link by email to download it and it is not shown in Setting -> General -> Advanced -> Export project. Could it be related? I also deleted a few branches, but I can’t imagine it would have this effect. No pushes were made during that time.

GitLab Enterprise Edition 12.10.0-pre on gitlab.com

We have the same issue. We have a pretty big repository ~ 17GB and currently gitlab shows that total size is 35GB.
Problem happened after I pushed local branch. Branch has minor diff with develop, and it’s impossible that diff was so huge to be >17GB. I tried to remove remote branch that caused the problem, but it won’t help.