Lets presume My customer paid online from his own computer. Now, I shipped the product also through USPS. I sent him the tracking number and I got the signed copy stating that he collected the package. Now can he file for chargeback stating : 1) Package didn't receive in proper condition ? 2) Package received but still wants his money back ? ( may be a scammer) 3) Customer claims as UNAUTHORISED claim. How do paypal helps seller in above cases ?