Service Interval Reset

The below shall hopefully give a starting point, please consider it as untested, though do come back and advise

Resetting Your Service Indicator Light

Step 1

Put your key into your car's ignition and turn it to the first position. Make sure your vehicle's mileage is showing.

Step 2

Press and hold the telephone button on your steering wheel. Immediately press the "OK" button and hold them both down for at least five seconds. If done correctly the shop menu will be shown on your display.

Step 3

Press the "Down" button on your arrow pad until you highlight the "Assyst Plus" option. Press the "OK" button.

Step 4

Press the "Down" button until you highlight "Service carried out." Press the "OK" button.

Step 5

Press the "Down" button until you highlight "Service due." Press the "OK" button.

Press the "Down" button until you highlight "Full service." Press the "OK" button. This should reset your service indicator light.

Note : Mines a 2019 250, with keyless entry
Just went out and checked, following the above procedure and it worked
Ensure you scroll through trip menu to mileage then reset your trip to zero
The below pictures is after scrolling through the menus