Extremely bad service

We ordered 3 x 300gr refill bags of Nescafe coffee on 16 January and paid the delivery fee but haven't received them. After waiting for two weeks, we requested a refund and supp**** bank details - no refund to date. We learned from an employee of Sunshine Cash and Carry that they don't stock 300gr refill packs, although it was advertised in their catalogue. It was agreed with that agent that an extra pack of 200 gr would be added to the shipment on 17 February and delivered on 18 February. To date, there has been no coffee, and their phone rings for 20 minutes before I end the call and call again. How can a business operate this way?