Bike doesn't change to speed display when riding

The display doesn’t change into speed display when riding.

The engine works.

If I don’t press any button regularly the screen will turn off and the engine will stop. Since it doesn’t go into speed display I can’t change speed mode either.

I changed the cable with the main plug to a new one since it was slightly damaged but this didn’t change a thing.

I also cleaned the speed sensor system but it didn’t change a thing.

Any ideas are welcome.