being blk listed for they fault

I bought two phones at cell c the grove mall late november 2014 we where not told about once off connection until now, first payment we notice it wasn't pulled, so we thought it will be done the following month and it wasn't pulled again they called in we told them there is money for the phone why are you guys not pulling it, they say the money is not enough they then told us about the once off connection fee which mean we don't leave 448 we had to leave 900 and something,after that we made an arrangement to deposit 600 and they will pull 448 from the account until the arrears have been removed, we deposit the R600 and then we noticed that the money hasn't been pulled, we went to cell c only to find out the account number that was put in the system is wrong and they now have blacklisted us for what is they fault in the first place, I AM SO DISAPPOINTED IN CELL C, its like they don't know what they are doing