"It was around 30 days"
It would have been preferable to refund the buyer at time the claim was filed for non-receipt. Both your eBay FVF and PayPal fees would have been credited.
"I also have another claim opened by purchaser credit card claiming not receiving it after more then two months... "
You'll have to deal with PayPal on that one. If you do not have proof of shipment through online tracking, odds are PayPal will find for the buyer.