Where is my refund???

On the 24th July I called multichoice to downgrade my package from Dstv Compact to Dstv Access and to cancel extra view. On the 27th July they still debited an amount of R428 instead of R110. I called on the 30th July and they said they would do a refund which will reflect within 7 days. I called again on the 12th August and they advised that the money will be in my account by close of business or the next day. Till today I have not received my refund.