Can I still cancel if I have already booked and paid?
In principle, no. There is no refund possible. This is clearly stated in advance in the booking screen and also in the confirmation. There may be exceptions to some specific incidents. At the location you can ask if you can move the booking to another time.
Reduction in the number of persons or quantity of rented E-choppers: This is considered a partial cancellation. Therefore, the cancellation rules apply here.
These cancellation rules are also in the general terms and conditions when booking.