Industrybuying com - I denied the delivery once because the order was probably made by clicking on a pop up but they deli

I am often ordering knives as i am a collector and there are ass and stuff on my phone i clicked on one and it took me to a website where i accidentally ordered a knife and i didn't want it and at first i didn't realise that the product was ordered then they started calling me to deliver i told them once that it is not my order then i stopped picking up their calls after that they came again to deliver it when i was not home and gave it to my mum and got paid for it now i have talked to customer care thrice they say I can't return it