Poor customer service

On the 24/2/2019 I went to the mall at carnival game to purchase a gas cylinder which was on special. When I arrived at the store, they were out of stock. The lady took down my details and advised that they will let me know when they have stock and I can collect to which I agreed. Yesterday, I received an sms stating that stock had arrived and that I can collect. I drove to the store only to be told that they do not have stock and I should go to benoni game. Is this how you treat your customers by giving them the run around. Who is going to compensate me for running around.