This message may be appearing because the power has not been turned back on at the circuit breaker. Make sure the power is turned back on to proceed.
It is also possible that the wires were not inserted sufficiently into the holes. When you have inserted them properly, the terminal tabs will become indented. Before removing the thermostat body and touching the wires, make sure the power has been turned OFF again at the circuit breaker. Once OFF:
- check the wires to make sure ¼” of clean wire is exposed and inserted
- check the terminal tabs to ensure they are indented