Sef 250 R 2021 motorcyle computer - odometer

Hi folks,

Could you help me with my issue. I've bought sherco motorcyle, unfortunately the LCD display doesn't count hours (ART) as well as other parameters (speed and milage). In case of speed, I imagine that there are no sensors on the front breaking disc. But more important is hours meter, do you know how it works and what should I check to repair this?

Best regards,
Szymon