Unreliable agents

Went to mtn mall of the north polokwane store did an upgrade on old top up contract the lady didnt do it correctly i noticed it within two weeks went back instore to query they didnt tell me the truth i found yesterday when i called call centre that she didnt put me on top up now mtn says i owe them and im sorry becsuse i cant afford to pay them as she mistake done by the consultant R2395.i trusted mtn i have been with for almost 8yrs and never had any issues when upgrading please help as i signed the top up contract,its a sales lady mistake en shich i realised that within two weeks snd never mentioned it to me just said lets wait until they debit i only realise that when i contacted call centre.i have been calling call centre to fix it they keep on promising me lies and the worst i did call them to arrange payment with them now they debit my account en didnt get the money and bank is charging me ,everytime when i call they r saying they will fix it from may until now so im tired mtn just be honest with me of you insist me to pay the money let it be abd then i cancel my contract as it is not what i signed for im tired of calling csll centre every week.<br>