Issue with Pre-order

Hi everyone,

I have a problem:

I pre-ordered 2 digital copies of Demigod to my impulse account. Today i received e-mail with only 1 serial number. but still my credit card was billed for 2 copies...

Product Name: Demigod (Pre-Order)  (Digital Download)
Product Price: $39.95
Quantity: 2

SubTotal:    $79.90
Shipping:    $0.00
Tax:         $0.00
Grand Total: $79.90

And where should i look for second key? I tried to get e-mail with all my registrations and still i get same serial which is already used in my impulse. Am i the only person who ordered 2 digital copies?? Pls help.