Moderation settings for a category do not save

I updated to the latest version.

I’ve found recently that users started to create topics and they didn’t come to moderation. I found that all moderation settings for any category were reseted. I tried to save them once more, but they reseted after some time.

Moderation
Require moderator approval of all new topics
Require moderator approval of all new replies

What may be the reason?
Does anybody face the same?

Update: I added settings for multiple categories. After some time all these settings were reseted.

Update2: checked on another instance and there is no such problem on 2.7.0.beta4 ( b7b81afe55 ) .

Does anybody have a clue on what’s happening with my Discourse? I can’ understand what to check…
These settings reset after some time: