Vodacom retentions cannot keep up to deals offered to retain customers

A few weeks ago I contact Vodacom cancellations to move over to a competitor due to my contract expiring and on average Vodacom’s deals are more expensive than that of their competitors. They were initially not bothered at the cancellations and I continued to cancel my current contract. I then received a call from the retentions department offering a better deal on the contract than that offered by their competitor and asked if I would be willing to reverse my cancellation, I informed them that I urgently require the device so if they can assist to arrange the device as soon as possible I definitely would stay with Vodacom. We finalised and approved the deal and after calling to find out a week later they informed me that the deal had been cancelled the day after it was made (without informing me or without sending any detail as the watch that came with the device was suddenly discontinued. I have been told that I can go to a store to get an upgrade meaning that I will not get the deal given initially and back at square one and the retention department still hasn't called back or bothered to assist. Vodacom is this the way to keep your customers???? by selling them deals that you cant live upto??