Foston won't Accelerate and always showing 1km/h

Hello, I'm having trouble with my Foston scooter (a replica of Xiaomi) as the accelerator is not functioning properly. It seems that the velocimeter is the root cause of the problem since it always displays a speed of 1km/h, even when I manually use the scooter. As the accelerator only seems to work when the velocimeter hits a certain point, I believe this is the issue. Can you please assist me in resolving this problem?