Double debits and still stories

My debit order did not go through end of Jan, I asked for a double debit end Feb. Saturday my account was debited twice with an amount of R200 and some odd rand. not my perscription fee and not my call account. Phone was still blocked on Tuesday. After calling the call centre my account was opened to be blocked again Wednesday. When i called after the phone was put down in my ear 3 times .... I was advised oh there is still an amount outstanding ..... I have been on time with my payments every month. Now this ...... i need to know what is going on .... where the outstanding amount comes from ..... still waiting for an account. This is really bad service. I had 3 contracts with Virgin Mobile and cancelled one after the orher. Be sure that i will not upgrade my account end June.