I've been using Bandhelper for several years (finger swipe style) with my old Galaxy Tab S no problems.
I also have Bandhelper setup on my Galaxy S21 Ultra phone as a backup.
I decided to add a bluetooth page turner to the setup. I chose a M-Vave Cube Turner.
The Cube Turner works perfectly as expected on the phone but not at all on the tablet.
The software 'Cube Suite' is setup on both devices.
I eventually gave up on the old tablet and bought an iPad Pro 11" (gen3).
I'm having the same problem with the iPad.
It's probably not a Bandhelper issue but I'm hoping some of the members here may have some insight.
It's incredible frustrating.
Did you set your desired actions on the Settings > App Control page?
More info is here:
https://www.bandhelper.com/tutorials/app_control.html#bluetooth
After a lot of tweaking with your suggestions yielding no results, suddenly it started working!
Phew.
Tx Arlo.