Bad attitude false advertising

Checkout Supermarket (Shallcross) advertised a ad for Johnson Baby Oil, Four 250ml and a 50ml free all for R50, I went to the supermarket numerous times and the people working their told me they had no stock and they will be getting Wednesday or Saturday i phone on Friday and they still did not have. i requested when i come there can she give me a credit note and she rep**** that they do not do that abruptly and she put the phone down. I am very angry at the way she spoke to me and how many times I had to waste my petrol to get there.