payment notification issue?

[MGBReg]

A customer has placed an order today and I received payment notification from Paypal but no notification from my cart.

I have checked the error log and the first part says:

Paypal webhook PAYMENT.CAPTURE.COMPLETED: order ID 371
Paypal related OrderId: 9X9762570K035825P but not found in the database.

Any ideas as to what may be my issue?

thanks Paul