my product has not been fixed

What happened was , I ordered a cloud9 not to long ago in December 2018 and in the space of a month I informed them to have it repaired for me and told them that I have a son and it could be dangerous , I advised them about the plug being damaged and it seems to have swollen up within a month and its a safety hazard. They then had it returned exactly the same as I sent it away and they sent me an email saying the return has been declined because there is nothing wrong with the product although I can clearly see if I continue using the flat iron it might burst and may cause flames because the plug is swollen.