Refuse to refund money that was taken without my consent

I purchased a phone last year at Canal Walk. The vendor asked if I would like to purchase insurance for my phone, so I said yes because it was an expensive phone. The insurance provider was The Foschini Group. I recently noticed that they were debiting my account TWICE every month, so I've been paying DOUBLE for my insurance.

I first alerted them to this error a month ago. I've corresponded with them SEVERAL TIMES via their Facebook page. Each time, they tell me that my problem has been transferred to the relevant department and I should be contacted shortly. I'M STILL WAITING. I phoned them SEVERAL TIMES as well. I've been told several times that someone will call me back, I've been told several times that I'm being transferred to the correct department but nobody answers, I've been told that the problem is being looked at. I'M STILL WAITING. I emailed them several times as well. The lady I was emailing seemed extremely helpful, forwarding my emails to the correct people, telling me that a refund IS owed and someone will contact me with details of the refund. I'M STILL WAITING. I don't know what else to do. These people have taken DOUBLE my money several times over a period of months without my consent.

I've cancelled my insurance with them, but I received no confirmation of the cancellation.

I don't know what else to do. I just want MY money that they stole from me. This is EXTREMELY frustrating and I don't know what else to do or who else I can talk to. I will NEVER use ANY of The Foschini Group's services EVER again, it's just not worth it.