Poor service

Poor service from On Air tv. I took two explorers and paying 139 for each. My debit order goes off on the 15th each month. Last month I received a call saying the debit order of last year June did not go through. I requested that because May is the last installment they must extend by one month to recover what they say I'm owing. For some reason last Month February a debit order went through on the 15 but on the 27 they sent another payment request and there was no money on my bank account but now I'm owing a bank R220 but returned debit orders. I tried calling on air to recover my bank charges but i can't get hold of them. I need somebody to answer to take responsibility for for the R220