Bad service

I'm so disappointed in herotel I never missed a payment but because I choose to eat my payments every month they decide to suspend my service. So now I'm struggling to get my account shorted out . They did the same to my father inlaw. How can sy tell me because the debit order did not go through I need to pay a additional payment because there system works like that. So what they are saying is that I must pay them a extra payment. As I said I never skipped a payment so why must i pay extra.