If it's been longer than 60 days since purchase, you'll need to go to paypal to open your Item Not Received case.
Oh, and DO NOT accept an offer of a replacement. It likely will not arrive in a timely fashion either. Nor should you 'close your case to get a refund' as that's not how it works. Close your case only when you get a refund confirmed in your account. And if you're feeling lucky you can use the refund to buy that item again from the same seller if it is still available.