The account is setup to use consolidated invoicing. The total of orders that exist to the statement day is 0 (e.g. there is a change order for -10 USD and a billing order for 10 USD). On the statement day the order with negative total was completed, no document was attached to it, order with positive total was not invoiced and was left in the status "Waiting for payment"/"Waiting for payment after provisioning" .
The issue is caused by the bug with id #PBA-82573 ("Incorrect orders processing in case the total of orders requiring consolidation is 0").
Contact Odin Technical Support to complete an order.