Bad customer service

I phoned this company for a settlement amount that was owed by me,i made the payment and on the 18thMAY 2015 received an email confirming that my account is paid in full and no outstanding balances.On the 8th of JUNE 2015 i phone the said company to confirmed if they send a confirmation letter to ITC to clear my name on this matter,just to be told that there is still a outstanding balance,i asked to speak to a supervisor and was told that they are all in a meeting,this is just unacceptable from this company and i want this issue resolved as soon as possible