I paid with PayPal but why is my invoice says Pending?
PayPal is huge pain sometimes when it comes to handling payments. They review a transaction for any number of reasons and they never tell us why. It's under "Paypal review" and shows it will be pending for 24 hours.
Maybe the payment was made from one state and the CC billing address is in another? Probably because credit card holder is first time buyer or unregistered with PayPal? stuff like this is why. Usually they will give a call to whoever placed the payment to verify.
If you want it cleared faster I would suggest to check your email for a receipt from PayPal and call them to find out. Unfortunately this is out of our control