Incorrect Statements

I have an edgars account with a limit of R5500, and it is a 6 month account. My installement this month is R2286, and there is no outstanding balance. The current balance is 4100. So this means over six months i will pay R13 716. Everymonth, despite paying above the installment, my installement gets higher. Emails to the account derpartment are returned with 'you need to pay '. Your accounts clerks don't read emails properly, don't offer to investigate neither are they the least helpful. They can't even spell correctly on official documents. I'm paying this account off and closing it. One more customer lost because of bad service edgars