I am trying to change some basic functions using Expert Coding in a Mercedes A class W177 from 2021 in the Head Unit HU6.

I am able to connect to the module and interrogate, clear errors, see live data etc but every time I try to change a parameter in the expert configuration, it says the coding was executed successfully, it resets the unit but after i check again the parameter, it remains unchanged and nothing happens. Is Autel Ultra Lite able to code functions on the head unit in my type of car? Does it have all security certificates (i do have an active license and the unit is up to date with all software). My Mercedes Benz software version on the tablet is v6.35- the latest.

Also i should mention i have not tried to activate advanced functions on the vehicle yet. As an example I have only tried to change the Head Unit language from German to US English - in order to make sure I am not trying to activate something else with dependencies on other modules. I have also tried to modify other small parameters that should not affect other modules but i get the same issue. I have also tried to raise the hood of the car, I have a battery robot to keep the voltage stable over 12.5V and so on.

Any help would be really appreciated. I do not know what am i missing here.

Thank you !