I've come back to work today and found an order from a few days ago consisting of about 6 lines with no product code, descriptions or prices.
it goes along the lines
2 x - (0.00)
1 x - (0.00)
etc
If I look at the order inventory, it shows all these items as having a product ID of 0, but my first product ID is 27.
I checked the order confirmation email and this shows the same.
I've emailed the customer to see if he did anything, or could shed any light on