I've not had this happen before. I ordered from a company I hadn't purchased from before. I had the option of PayPal or credit card. I opted for credit card as if there's a problem, the response time is much faster. I just received an email showing the purchase was made using PayPal which uses this card to cover any overages. Is this normal?
If you bought something online with a debit or credit card and did NOT log into your Paypal account then of course it won't show on that Paypal account because you bought as a 'guest buyer'. However your seller may have processed that payment using their Paypal 'card reader' and so Paypal would show on your bank or card statement.
Advice is voluntary. Kudos / Solution appreciated.