W213 dashboard unit changing from miles to km .

[Hnerty]

Hello guys

Not sure if anyone encountered this problem , seems to be common and MB don’t have a clue
W213 , dashboard keep changing form miles to km ( I know that is a German car !) and every time morning or when I leave the car for an hour or so it’s keep changing
Anyone any idea why ?
Tried several tips nothing worked
Thanks

 

[Stratman]

How old is the battery?

 

[Hnerty]

How old is the battery?

A month old

 

[Stratman]

Not that then