Siemens brtrf keep LOSING connection?

Why does my Siemens brtrf keep LOSING connection.
I can re-attach using learn OK, and then it stays connected for 1 hour to several days, then drops out again.
Tried 2 sets of new batteries, doesn't make any difference.
Had previously worked OK for ~6 years
Duggle, August 2022


done
https://www.justanswer.com/uk-plumbing/9jfyj-brian-problem-thermostat-bps242rf.html

Rruru, August 2022
link Click here to see other fixes for Siemens.