Blocked for no reason!!!!!

I don't even know where to start. After numerous account queries, my account was yet again debited earlier than expected. My contract states month end, not the 28,29etc. "SORRY SIR, IT WAS SONE VIA OUR COLLECTION DEPARTMENT". I asked to please fix this issue, and send me a new debi check so we don't sit with this problem. It is now the 17th of May, and yet my number still blocked (but my account is not in arrears,paid up), and no debi check received as yet. BAD SERVICE!!