Taking MY money.

I had an account with Mrprice and have settled my account in full.I overpaid them and they send me a bill stating that I was in credit for the amount of R307.29. Now all of a sudden my credit is less than R150.00 because they have used MY money for "klientebekermingsplan".If I had no credit how would they got money from me for the "plan" Also they ignore my mails and I want my full R307.29.That money belongs to me and they are busy *****ing my money.Monies that belongs to me and not them. Waiting for your response. Thank you, Heinrich Smit. ********** .