I’m very tired today, so I’m not going to be able to answer in detail at this time. Maybe tomorrow or the next day. Hopefully someone else will join in before then.
Meanwhile, we had a very recent thread from a community member who was having problems with some zigbee sensors, and we got into a number of detailed discussions about how Zigbee repeaters work that might be helpful to you. So skim through the first few posts to get an idea of what problem is being discussed and then you’ll find the discussions about Zigbee network strength.
Newbie: Cannot pair Xfinity XH52-UE Sensors
And specifically, with regard to your buttons, make sure you read post 65 in that thread:
Newbie: Cannot pair Xfinity XH52-UE Sensors - #65 by JDRoberts