Summary field not updating on Edit

I have a summary field that collects the info from other fields.
It works fine but when users Edit the info the summary is not updated.
Funny thing is that when I do it (test entry) it works, but not on a user level.
(I am admin, they're users)

The field is not updatable on edit script either.

I have other applications for which it works, but I can't get round to figuring out what could be wrong...