Refusal to close account after settlement paid

I requested a settlement letter from Game which I received the 29th of May. The payment was made on the 30th of May and I provided them with the proof of payment. I only received a response on the 11th of June, even after the promise of a response within 48 hours. When I phone they tell me to email so there is nothing I could have done to speed up the process. The response said that they will close my account in the next 36 days but my balance will remain zero. Knowing Game is tardy with account closures I thought nothing of it. Today 15 June I received a bill of R70.36 ??? I paid my settlement amount. I requested the account to be closed. Now you are billing me??? When I responded to this email I received a reply about how to check my balance via cellphone banking. I am trying to get out of debt and you are ******** me for more money. I expect this to be resolved before my debit order date on the 20th where after I will go the legal route.