Tado thermostat doesn't ask for enough heat

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Hey all,

Yesterday I noticed the room getting a bit cold.

I checked the app and I saw a difference of 4C of what is being asked.

It's requesting heat but radiators are cold, heater isn't burning, but it does work when I need hot water (not tado depended). When I remove the tado from the connection, the boiler heats up to 65°C. When connect it back it drops to 40°C. TRV do go open when asking heat.

I checked if the wiring is still in place but it looked fine.

The only thing I noticed is that 2 cables were switched up but it worked before.

Just to be sure I tried switching the cables but no luck.

The heater doesn't indicates a alarm or error.

I don't understand how the wiring was wrong but that is was working for 2 months.

Setup:

Tado V3+ thermostat (wired)

4x trv TRV move when requesting heat

I tried deleting the whole configuration in the app, turning the heater on and off, turning thermostat on and off, reconnecting wires,...