Strange behavior

I use a switch from Nexa in the KlikAanKlikUit app. The switch behaves in a strange way. If I stand between the switch and my Homey then the switch works, if I go to the side and do not stand between the switch and Homey, it does not work. The distance between the switch and Homey is about 3 meters, with a light wall in between. Has anyone experienced anything similar?

It might be similar to this: when you want to open/close your car remotely, and you’re a little out of range, the car doesn’t respond. However, the car does respond when you hold the remote to your head while pressing the button.
(Something with water and signal spreading).
In your case the wall seems to be to much of a signal disturbance / blocker.