That's really strange....I mean, if you log in to your paypal account, can you see the transaction on the recent activities list?
If not, are you sure these emails are coming from PayPal directly? I've had situations where I get fraudulent emails about things, but when I log in to my actual account (always via bookmark or googling for the site), it was clearly a fake email....
if you don't see it, is there any evidence in your balance of missing money? If you do see it, how can PayPal claim not to see a debit that their website shows?