How do you open a case against the seller?
You can go ahead and open a case, but first you might want to make sure the seller understands that you need them to change the PayPal associated with Ebay. You can give them a day or so to make sure they receive that message but probably not much longer (since you as a buyer have only a limited time to pay for an item before the seller can open an unpaid item case). If you've asked them to change their PayPal, have they refused to do so or are they dragging their feet? If so, you should probably open a case right away.
You can go to your Purchase History (under My Ebay) and find the auction in question. Then, click on the small "More Actions" option on the right and say "Contact seller." This should bring you to a page where Ebay will ask what you want to do; you can choose the option "I didn't receive my item," and then Ebay will provide you with a link to request a refund or more info from the seller. I'm pretty sure that once you choose one of these options a case will be open, which you can check the status of in the Resolution Center (on your Account page, under Summary under My Ebay.) (If anyone knows a simpler way to do this, post it here
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