Fibaro dimmer switch wall switch behavious

Hi,

After installing a Fibaro Dimmer 1 I can control the lights (three wall lights controlled by one switch) via Google Assistant and Smartthings App fine. The problem I have is when it comes to controlling the lights via the momentary switch I have installed with it.

To turn the lights on I seem to have to firstly press and hold and then press again. The lights don’t turn on until the second press after hold.

Similarly after the lights have been on for a while, to turn the lights off I need to do the same. Press and hold then press again.

Oddly, when I get the lights on I can turn them off straight away with a single press. On/off works fine until the lights have been left in a single state for a while.

I’ve tried a couple of different handlers but no joy.

Thanks as always in advance!