cannot create tags with webui ~7.12.2

Hi

a bit similar as issue #1851 (closed) (mentions only gitlab.com) but related to gitlab CE 7.12.2 (from source) , i cannot at all create any tags with the webui and keep getting invalid reference error. creating tags on command line works. I however tested with several projects and alas no tags possible. Anything i can do ? apologies if this is duplicate.