False advertising

I was interested in the R99 contract for 20GB a month including a router. I called the Westgate(western-cape) mall branch on the 19th of this month and was told that they don't have stock but will be getting in the following week and took my details saying they'll contact me when stock arrives. On the 22nd I decided to call the canal walk branch to find out if they have stock only to be told that the deal has ended that very same day. I then called the tygervalley and vangate branches to be told the same thing even though the ad for this contract states that it ends the end of May. I then went back to westgate mall to be told the stock theyl be receiving is for people who are already on a waiting list yet I called in the week and was told I'd be contacted when stock arrives and to bring in the required documents. Its been a complete was of time and a very disappointing weekend finding out I can no longer sign up for this contract. What kind of company advertises something for said amount of time but then out of the blue just decides to discontinue it. horrible and absolute bad treatment of customers.