Unable to assign moderator

Hello,

I have migrated my site two days before and since than, I cannot assign moderator to the question.

Question shows, there is no moderator assigned - it is ok, when I click to dropdown menu - it shows all moderators, it is also ok, but when I choose one of them, it is not assigned to the post and there is still message post have no moderator yet.

The same situation apear when I try to change moderator. Nothing changes.

Is it possible I have corrupt some file when migrated?

Also, I did migrate almost 25.000 new questions and replyes - directly to the databse (but just to the #_discuss_post table.

But it still seems, there is somethign wrong with javascript..

Thank you for advise

Best regards
Pavel