Extended service plan cancelation

Last year i bought a demo Ford Figo 2018, took out extended services plan for it wich is supposed to be for next year as the car comes with a 2 year service plan, I in august asked for the extended service plan to be canceled and for the amount to be refunded back to the bank, I was informed they can only refund a pro-rata amount, how can they charge me a pro-rata amount, I asked their finance person Faieza in jhb Ford to explain how come I am billed for services iv neva used, she also didn't have an answer for me said it's Ford credit that dose journals she emailed me this Contact and said I must call them and ask, wich I tried to call them a number of times no one answers this phones, I am so frustrated as I need my full amount to be refunded back