Cell C is pathetic

i have had a major issue with Cell C for over a month now, it has taken them more than a month to allocate my 2 payments that were done via their website, in the meantime, every week the still put the debit order through on my bank account, i have had to move all my funds to another account just to stop duplicate payments (which will take another 3 months to sort out), they have now cost me R840.00 on bank charges, why should I be held liable for these costs if i did pay the accounts, yet Cell C still continues to put the debit orders through every week (for the amounts that have been paid)????