I have ordered 2 things from eBay but I forgot to change my address I tried to cancel within minutes and send my new address to seller same time also keep asking for help to eBay but nothing happened. I made mistakes to order on eBay
The seller should cancel, you update your details and they relist for you to buy again. If they won't do that I'm afraid there's nothing else you can do. It's up to buyers to make sure their details are correct.