Evotouch ambiant température is showing wrong ambiant / going in opposite direction

Hi there,

Today I had to power off my BDR91 to do some electrical works, my evotouch went on battery mode, and since I powered on again, I see the temperature of my living room (having 2 heaters) is just going in the opposite direction / Showing an incorrect ambiant température.

In the facts, my evotouch shows 23 degrees for the living room, but the temperature is I am sure not more than 19 or 20 degrees ...
If I open the window, it detects the open window (shows the window icon) but the temperature showed on the evotouch is increasing to 24 or 24.5 degrees ... instead of showing a less temperature ?!?

I checked the 2 HR92's I have in the living room, they are "in sync" with the Evotouch and showing a correct demand temperature of 20 degrees, but if I change the parameter 7 to show the current ambiant temperature, they also show like the evotouch 23 or 24 degrees ...

It is the first time I see such behavior in 5 years utilisation ... any idea what the problem could be ?
Is there a way to "restart" the evotouch without loosing all parameters ?

Many thanks !