Hi,
1. No array filter, but subquestion relevance (I changed the question Code to Q1,)
2. Don't set "array filter type" to "hidden", but "deactivated"
3. A setting of "min. answers = 1" is obsolete, if the question is mandatory.
Of course you have to check, that people do not select
Region 1 and
Region 2.
Instead they should have selected the first option "
Region 1 and Region 2"
They same with the districts.
So I recommend to change the design of this question.
There is a possible example in my "Tutorial 2: Mehrfachnennungen..." (German section)
See the video on page 13.
Joffm