Dstv poor service

I have a contract with dstv As i am a pensioner is asked for a debitorder for the last or first day of the month. For the past few months my debit order goes through before that and is declined by my bank. As i live where cell reception is very poor i communicate by e mail. I laid a complaint by e mail but they don t bother to even reply on my e mail. Every month this is costing me money. They are an ******** company or thier workers just dont care