Bad service

I have been doing my senior amended certificate with them I had called them several times to tell them I haven't received study material for one of the subjects. I had to write my exam without the study material and I had asked them to give me a refund on that subject as I was still paying I asked them to inform me how much the refund will be before I make payments again I owe the 2000 and now they just keep sending me emails and messages that my account is in arrears which I haven't received a call from them about the refund