If your scooter is beeping and won't move under its own power, by far and away, the #1 reason is because the scooter is in the neutral (free-wheel) position. The easiest way to verify this is by removing the key from your scooter and attempting to push the scooter with your hand. If it rolls, the scooter is in neutral and will not operate under it's own power.
If this is the case, remove the key from your scooter, and then locate the drive/neutral lever on the rear of your scooter. Move the lever to the drive position. Now you will find that you cannot manually push the scooter but that the scooter is now restored to power operation.
Typical drive/neutral lever appearance and labeling: