Airbnb service fee

Good Morning. We made a booking with raven house in plettenberg bay in south Africa and unfortunately we had to cancel the accommodation. This was done several months before the booking was supposed to happen. I asked raven if their would be a cancellation if we cancelled way in advance. He phone Airbnb to be told that there will be no charge. Instead we receive a £155 service fee charge which is utterly rediculous and EXTREMELY expensive to use this service where 99% of bookings apps have free cancellation if done early enough. Please investigate as this is highway ******* and ******ion.