You can search for Sellers via the Advanced link to the right of the eBay Search window. Scroll down to the Seller section and enter the ID and complete the Search at the top or bottom of the page.

The quickest way to search on eBay is by using our search bar at the top of most pages. Type in what you're looking for, hit Search, and we'll find the items that best match your search.

Find the item in your Purchases. Select See request details (if your item didn't arrive) or See return details (if you're trying to return an item). Select Ask eBay to step in and help. Select a reason from the dropdown menu, then select Confirm.