Billing Document pricing issue

We are having the issue with some of our deliveries and the issue is random. When we trying to process multiple deliveries in VF01/VF04 sometime price is coming zero in billing document from delivery. When we are doing an analysis of pricing condition in billing document it says condition record is missing.

We tried to process the delivery individually in VF01, the price got copied to billing document. Can anyone suggest what could be the issue?