Reneging on settlement offer

On 2 August 2017 I made a settlement offer to Edcon to close my Edgars account which was accepted on the 4 August 2017 by Nkosiphendule Seja in writing. I provided proof of payment and requested confirmation of account closure. I was repeatedly told by Nkosiphendule that they waiting for the discount given of R946 to be written off before the account is closed. I subsequently was advised by Nkosiphendule that she thought my account was under debt review and gave the settlement offer and it was a mistake!