I looked for the same topic and I see there are several related subjects but posted in 2018.
I am struggling to make my sync filters work. I managed to make them work in another report but with this one I am unable to understand what is wrong. I have a dimension table with unique values which is related one-to-many with the rest and unique filter direction.
I have a slicer containing the unique values table and sync with all of the pages. The first sync works in all pages but when I select another value, the tables of pages that are not in that of the slicer, appears in blank so the sync is not working (it is stuck on the first selected value). I checked if I had any hidden filter but I do not have any.