Bad to the bone

I been trying to win this flamethrower and won the auction but now that iam trying to finalizing but it just gives me the same thing saying that it might be a steam issue or a trade url issue buts its not my trade url because i updated it and verified it by selling items to scrap and works perfectly no item from the auction has been traded or lost they are still in my inventory and i been going for 4 hours now and still nothing hopefully i get help