Contract upgrade

Was due for an upgrade and went to the Eastgate store and took a phone as a gift for my partner. Wanted to return the phone and exchange it for another and continue with the contract but to my surprise I was told by the assistant manager that once I leave the shop I am stuck with the phone, happy with it or not I am bound by the contract I signed. He never even asked for my name or the name of a consultant that assisted me at any stage or asked me if the terms and conditions were explained to me all he said was what were you signing for when you signed? He informed me that he does not have money to pay for that phone and they cannot take it back as they do not sell second hand phones in the store and I was surprised to be asked this by a manager and asked about their after care sales for their customers. I was never at any stage of the contract informed about the none return policy and that as a customer am not allowed to return a product that I am not happy about not for total cancelation but an exchange for a suitable device that will fulfill the personal needs for the person using the device. I did not even want to downgrade but take something within the same price range. How am I protected as a client who has had contracts with this service provider since 2010, I am very disappointed with the treatment I received from Vodacom. Prior to going to the store I called customer service and they could not assist me and transferred me to the after sales department that gave me excellent service compared to the arrogant straight decline i received at the store and the call made to customer service was after I made the call to the store where I spoke to 1 person who told me that I can come to the store and try my luck but does not think its going to happen. Why does it have to be luck when as a customer am not totally satisfied with my purchase? The manager went as far as telling me that none of those people I spoke to will pay for the phone but him and he does not have such money as this has happened before. I was very disappointed by the service and I went as far as asking for him to just go through the footage and tell me if the time spent with the consultant could indicate that all terms and conditions of the contract were explained and he said there is no audio and those cameras were not used for such. I asked that we must just check the time I spent and tell me if it's possible that all important information was shared and he said he can't do that. I explained to him that a terms and conditions link was only sent to me after 6pm and how was I suppose to have read them if the sms was sent after leaving the store.