Refund is an issue

I have been a DSTV customer for over 7 years and I have never skipped any of my payments. In March I was offered a Price lock deal for R450 which I took. I was informed that they will start debiting the R450 in April, to my surprise they debited R731 which was not the agreement. When I called they couldn't explain the reason why. They told me that they will refund me as they can see that there was a credit on my account. Now, 4 days later there is still no refund. I called them again today and the agent tells me that I must email my bank statement and ID of which the initial agent didn't tell me to email. I am very disappointed in Multi choice as it seems like I have to be sent from pillar to post before I get my refund.