Not honouring promoted deal

In short I've been trying to upgrade my contract with a sales lady (Ms Thokozile Boblani) since the beginning of December 2014 and to upgrade with a Sony Z3 compact free Sony android watch or headphones which was running till the end of January 2015. The problem was that they were out of stock of the watch and could not upgrade me till both units was in stock, I did try and tell them to go ahead with the upgrade and that they could deliver the watch when it came into stock but she said that we have to wait for both to be in stock. Where my frustration came in was that I had to call them weekly to get feedback and not the other way around. A week before the promotion ended I was bluntly informed that this promotion was no longer available and that there was nothing they could do, I was referred to the manager (Mr Mzazi) and tried on numerous occasions to speak with him as well as leaving messages but have not received a call or explanation till now. I have been a loyal customer for more than 8 years (with the same number) and I feel I deserve better treatment than this. All I ask is that they honour the deal I waited so patiently for them to supply me and not ignore my pleas.