I shipped a t-shirt First Class Mail with delivery confirmation from CA to Florida. It's been almost 2 weeks and tracking information shows it was accepted and processed, but no other info is available. Buyer is getting very angry and demands that I refund him immediately because ' it's out of control' and he is not willing to wait any longer. Do I have to refund and take a loss even though item may still turn up? What are Paypal requirements?