The first impression was that the cap of the dimmer is very shaky. A training to Home Assistant by Zigbee 2Mqtt worked without any problems and after a while all functions were available. Unfortunately, the dimmer with a button reacts only very unreliably. Sometimes it works, sometimes many seconds later, sometimes not at all.
I will dispose of the button and replace it with another, as this does not ensure reliable function. Can be.

Works

very good product for this money

A practical and very sensible insurance, I recommend to everyone. For installation, read the qr code in the box or booklet download the application, add the device, and hold down the fuse button 5 seconds during the search, let the device start flashing blue and release it will find.

It is okay it is a bit complicated the configuration of the parameters of the device but it has step