Cell C
Duplicate contract debit orde

I had started a 500mb data contract at the beginning of july. There was an error with the monthly fee that i was promised. The matter was resolved and i was made to take out a new 500mb contract after being promised that the first one was cancelled. My debit orders went out today and i got billed twice for sim and connection R114. I was promised the contract was cancelled by blanch opperman from head office. Why am i billed twice when im only using one contract. I want a refund