Thermostat keeps given ON signal

Beekie

My thermostat seems to keep giving the ON signal to the boiler.
It clicks when i raise the temperature but doesn't click back when lowered, causing the boiler to stay on.

Only when i restart the thermostat (10 second press) it seems to switch off the signal.
Causing the above process to repeat once raised again

samd

Sounds faulty. Use the chat line on tado.com and, if so, they will replace if under warranty