Advertising of goods that is out of stock

I have cancelled my contract from Vodacom due to bad service, and asked MTN to take over my number. My husband was already om the MTN network and we were advised that we only open another line on his account. During December / January MTN advertised J1 Ace on contract then you get another phone with it. After opening a new line on 3 January 2016 we were told that they are out of stock and that we must follow up in the week. On Wednesday 6 January 2016 we were told they are still out of stock and that the they will have stock by the weekend. On Saturday 9 January 2016 I requested the consultant to source the phones. We waited for an hour, and after no service we eventually left the shop. Still with no service. This is a second year in a row where we had to wait for stocked which is still being advertised in the broachers.