Incorrect Settlement Amount Provided-VERY ANGRY!!

03/03 i was supposedly given a full settlement figure & told when to pay it by & to email proof of payment.I did all of this the following day.I was not told that due to your systems being down IN FEBRUARY there may be additional charges not included,or that this was a provisional figure only.When submitting the proof of pment i requested for the account to be closed.I received an acknowledgement of my mail & further emails thereafter from other consultants requesting for my ID no in order for the account to be closed.I responded to each one with my ID no.Nothing was heard from you again until i received a statement on 29/03 showing another \outstanding balance"of R302.53.I again made contact with you yesterday only to be told that due to your system error IN FEB"