In some change orders, there is a missing value for 'unit price', for refund lines.
This is expected behavior. It is the result of the Unit Price changes.
i.e. customer purchased some resource at certain price. After that provider has changed resource unit price. After that customer decided to stop using resource and placed a resource downgrade order. If this is done within "Full Refund" period - BA finds that resource had two different unit prices within refund period.
Due to this, neither of two unit prices are shown in the refund details. BA also does not calculate "Overage Resource price", because such price never existed, and may mislead Provider or customer.
Instead - only extended price is calculated.