Upgrade not done as promised

I received a call from Cell c to offer me an upgrade deal which i chose Galaxy S7 n i was promised to receive a voucher of the free 3D virtual viewer or simething, this happened on 22-03-2016. Delivery was done 2days after n only to find that the voucher was not included in the box . On Monday i kept calling to make a follow-up and i was told on the day of offer the free 3D gear was no longer on special but they will see what they can do to correct the mistake, after frw days i called again sonce there eas silent i left messages for Amogelang but never called back till last when i demanded to speak to the manager they said they cannot do anything to help me but offered me 1GB of data for 24months. However i declined the deal due to the reason i tool an upgrade of S7 cause of the free gear, but now my problem they not contacting me i always have to run after their back. All i want is the gear and nothing else or i am returning the phone back and cancelling my contract simple!!!!!