Baxi cannot be turned off via the power off button

Hello,

My boiler, Baxi Luna Duo-tec 1.24 E, is controlled via OpenTherm using the tado wired thermostat. Heating and DHW control works fine.

I noticed that when I connected the thermostat via OpenTherm basically the boiler cannot be controlled via the HW buttons located on the front which is okay and expected, however also the power off button does not work, so I cannot turn off the boiler. Is this common behavvior aross the boilers ?