Vodacom Bayside BAD serivce

On Saturday 4 May I went to Vodacom in Bayside to apply for the GB data top up plus router. The quoted price was R329 for the router plus 90GB data per month. I filled out all the forms and had all the supporting documentation but the vetting was pending. I was informed that there was a problem with the system, but was assured more that once that I will still get the deal that was only valid until Monday 6 May. On Monday evening at 18:55, I received a call to inform me that everything is ok and I can come in to collect the router and sign the contract the next day, which I did. I received the router and simcard, but on Thursday 9 May, I received a call to tell me sorry but the deal is not available to me as I only signed the contract on 7 May. This was through no fault of mine, but now Vodacom refuses to honour the deal. This is totally unacceptable as I was not at fault for the delay.