Communication problem with Heatit Z-TRM2fx thermostats

[Olex 0]

Hello.

I’m using an HC2 with some additional Fibaro hardware.
I have also installed Heatit Z-TRM2fx thermostats, and here I end up with some problems.
My house has three floors, and I have one Heatit Z-TRM2fx in each floor, the HC2 is placed in the second floor.
I start adding the first thermostat in the second floor, which is close to the HC2 (approximately 2 meters).
Using this thermostat for one day without problem.

Then I added the thermostat for the third floor and that also worked fine for one day.
This thermostat is just above the one at the second floor, approximately 5 meters away.
 
I then add the thermostat for the first floor and that worked for a few hours, gets “communication problem”.
I also gets some “transfer failed” and “communication problem” for the thermostat in the first floor.
This thermostat is placed approximately 5 meters underneath the thermostat in the second floor.

I removed all devices and start all over again, the same sequence, starting with the closest thermostat (second floor).
The result is the same, it works for an few hours.

Is there any advice adding powered devices, should I start with the unit far away first?
I have also tried to perform Mesh network reconfiguration, that doesn’t seem to help.
Any suggestions?
Should I check for “Device is located far from the Home Center” and/or “NWI - Network-Wide Inclusion”?
 

 

Thanks and regards from Norway,
Olex