Mobile Slide View (One Review per Slide) has no effect

Hi there!

I am running the latest paid version of WP Review Slider Pro, and three reviews per row.

I would like to only show a single review (not all three stacked on top of each other) on mobile, however, the option for that (Mobile Slide View (One Review per Slide)) has no effect. Either or not I checked it, it always shows them stacked above each other.

I found https://wpreviewslider.userecho.com/en/communities/1/topics/1071-one-review-per-slide-is-still-showing-trhee-stacked-reviews - but even if I disable Combining Javascript and purge the cache, it does not help.

Anything else that could interfere here?

Thanks!

BR Sören