Driving school refuses motorcycle riding lessons !!!!

Hello, I passed the theory exam for class A without any restrictions in December. Since then the driving school is waiting for the weather to improve so that I can start with the driving lessons, in the last weeks it is actually not so cold anymore (come from the Ruhr region) and I have addressed my driving school several times and that I always think that the weather should be even better. are really 10° Temp. too little so you can drive ? I don’t understand my driving school meh r.