MTN false adverti*****t

I've been shopping around for a tablet for the past 2 months now since my tablet contract with MTN terminated. I eagerly await the 1st of every month to checkout the latest deals on Yellow Trader. On the 1st October 2017 I downloaded the Yellow Trader and started browsing through the deals and came across a tablet that I wanted to get for a very long time, Samsung Galaxy Tab A with S-pen. The tablet is advertised for R149 pm x 24 on MTN MyChoice 500. MTN refuses to give me this tablet contract that is advertised currently on Yellow Trader October 2017 edition. I called MTN Direct sales and was sent around in circles and put on hold for a very long time because these clowns cannot find the deal advertised on Yellow Trader on their system. Why advertise something and end-up disappointing your customer because you made a mistake and failed to correct this by removing the advert or placing a notice on your website??? I'm using MTN over 10 years now and I am very disappointed that they would do this to me. :'(