Bad service and false advertising

Hi we have bought a 6-litre fryer which was not the right size when we received the air fryer it was a 3.8 l and stead of a 6 l .we had numerous issues with the call centre and we spoke with a guy at head office that promised me the moon and the stars we returned the product 3 times and go sent back the same wrong product when i try call them now and ask for someone to call me nobody does