Vodacom took the liberty to put my account on cash

I called in November 2015 to update my banking details with Vodacom. i was told it was done as per my request. in December i was not debited on either my new or old banking account which i noticed myself so i called to query. i was told they didnt debit me but they dont know why and they would go in for a double debit. i was also told that my new account details was not updated as per my initial request and they would log a call to have it done. on the 2Feb16 my account was soft locked due to being in arrears. when i called to query, i was told my account has been a cash account since december, and they were expecting me to pay in cash and therefore i am in arrear because of none payment. i am not expected to pay a substantial amount in order to get my account unblocked. no one is giving me correct feedback and im very upset about the manner in which the call centre agents handled my queries. i was told they can not pick up the voice recordings from all my previous calls either.