Service Costs

I called to book my car in for its annual service. It has a low mileage of 22400km, with the service plan stating that only at 45000km would the service have a cost. I was not informed of any cost during the booking call. I was only informed once my car was being signed in at the service centre. I find this very misleading, and was very shocked to learn that I am expected to pay over R3000 for a service I have not budgeted for.