Hi . it must have lost connection with the reciever
Take the room stat off the wall, take out batteries . take it to the reciever box. Hold reciever button in for 15 seconds. Led should flash fast . then hold button in for 5 secs, release. Put batteries back in stat. Press the learn button on back of stat .this should reconnect.
Hi . did this work?
If so , would you mind rating my answer ,thanks