Capitec hidden amounts

I had a loan with capitec that took too long for me to complete due to losing my job. I finally settled the account on the 22nd of July which had an outstanding balance of R17 350. I later received an sms stating that my account was in arreas with R149, I transferred the amount stated into their account. 2 days later the amount was returned to my account and the app showed a balance of R0.00. I call in today requesting for a settlement letter and the consultant says I should have requested for a settlement quotation before making a payment and my account is in arrears because I did not do so. The app indicates that I have no outstanding balance and no arreas so I am confused and worried that they are using this to de***** their customers. All I want is a settlement letter so I can close my account with them I can't keep complaining about their *********** behaviour.