I looked at the topic, but there is nothing in the database tables of this order.
Today, two orders came in from the same customer. Both were paid with paypal, but only one invoice has been created. The first invoice has not been generated and can not be seen in BC or in the databases. The customer has only paid.
A previous order was sent out with the previous invoice number. Then the second order bill from the customer above. The first order bill is simply missing.