MTN - Charges deducted but no phone delivered

MTN's call centre CCI sold me a phone deal in August 2017, they had various issues delivering the phone i ordered. They have been charging me R299 since the upgrade but i have yet to receive the device. I have been in contact with MTN, i cancelled the upgrade in early January 2018. They keep saying that they will cancel and refund/ credit me with the deductions they have been making since August 2017. I call once week to check the status, and nothing has been done. When they say they will send an sms as confirmation of authorization, i never receive an sms. My most recent reference number is SMC ********** 8970, please, for the love of god, will they just cancel the upgrade and re-imburse me?