False advertising

I went to upgrade my Vodacom contract at Chatz Connect in Vereeniging on friday the 16/10/2015. While the service was very good in store the systems were slow and the consultant told me that he would continue to process the quote and let me know when I can come back in to sign. <br> <br> As I arrived home I recieved a call stating that everything was done and that I should pop in in the morning to sign. I did so only to find out that the deal in the flyer is only for new contracts. This is not stated anywhere on this specific special. I understand that this is not an issue that the branch can sort out as they are only following instruction from the head office. But this is still extremely frustrating, and I cannot find a number for the head office in order to raise this where it needs to be raised.