Hi, Thanks a lot for the fast responsive..
I've tested the situation on two different systems, because I'm planning to move my mediawiki as soon as this problem will be solved. Therefor, I'll have 2 answers for your questions :)
My MediaWiki version is 1.28.2 (tested also on 1.31.0 which I'm planning to be moved for)
AutoCreateCategoryPages version is 1.0.1 (tested also on 1.0.3)
UserFunction version is 2.7.0
I don't get any massage, and I've noticed that the whole functions of category doesn't work. What I mean is that once UserFunction is installed, as well as the AutoCreateCategoryPages which don't create pages, also other functions as adding a page into existing category doesn't work... Once I remove the UserFunctions from LocalSettings the MediaWiki starts doing the magic...