When I tried to pay for an item, I was not allowed to pay as the seller had not specified postage costs for my delivery address. When I contacted the seller, the seller replied that postage was free of charge. I am still not able to pay for the item. I have asked the seller on several occasions to change their settings so that I can pay for the item. The seller has not done so and now has opened a claim against me for not paying for the item. What should I do? Thanks