Last night some one had found an offer at asda for a Nivea summer essentials pack marked at £5 each or 3 for £3. So I did a bit of grocery shopping and added 6 to my basket, the offer was showing on my total so I added more items as the minimum order is £25. My shopping has just been delivered the driver handed me the receipt and on it the Nivea packs are priced at £5 each so £30 in total. I explained to the driver about the deal and he said someone would ring me. I obviously didn't keep any of the 6 packs and the driver requested my £30 refund. Are they within their rights to do this or have I got an argument? I have got an order conformation showing the saving, or am I wasting my time?