Billing is being posted to the wrong account...?

After the sales order is being created and prices calculated, I notcied that account is being posted in the Export Sales instead of Domestic? They're both under ERL, but what could cause this? Or the better question would be, where can I go to configure it correctly? Is it in the pricing procedure or the account determination process? If anyone could give me an answer, I would really appreciate it. Thanks all.