Trunkies for £10.67 instore @ Argos!

Trunkies are usually £40 Get them for about £10 from Argos!! Argos have reduced some of them to £31.99 and they are also on for a 3 for 2. However when you go to pay at the till each individual trunkie comes up as £16 (exactly) before the 3 for 2 discount. I have bought a few today see attached receipt. And as they are on a 3 for 2 each individual trunkie is just under £11. I paid £32 for three items! And usually one is £40. Some people would not believe me so i took a picture of the items on the receipt so i may as well share it with you guys too. The three for two runs out tomorrow so you need to purchase by then. I think it is a pricing error perhaps, i have taken my reservation number off incase the powers that be hunt me down (lack of sleep makes me paranoid!). Good luck.