Contractual obligations not met

I upgraded my contract on 20 November and was told that I will get a R 2000 take a lot voucher. I asked the agent numerous times if there was any catches and said no, will get an sms within 7 working days for this. Beginning December I had heard nothing and phoned again, I was then told that it is 7 working days from the date that the contract activates. Wait again and nothing. Phoned again on Monday 13/12 and speak to Yuleesa, promises feedback within 48 hours, heard nothing again. Phone again 15/ 12 and speak to her again, told that it was escalated to her manager and name is on list and sent to Vodacom for the voucher. Heard nothing by today and phone again and speak to Kuven, on the phone for an hour and he was "Checking with his manager" and call cut, no decency to phone back and provide feedback. Oh, the story that I was told previously was also different. Phone again today and speak to Yuleesa again, just says nothing they can do as been escalated, waiting in anticipation for Kreshan to phone me