21-11-2017 11:19 AM
Log directly into your Paypal account and click on "Resolve a problem in the Resolution Centre" on the lefthand side. Open a "Not received" case and escalate it asap within 20 days.
You have 180 days from date of payment to do that so you could wait and see if you get the item if you prefer, although if it does come it could be fake if that's relevant. If so I'd do it now.