To remove a transaction from a billing run, you must open the billing run, you can do this by:
From the Toolbar select Sales Ledger
Then select Postings
Select the Billing Run in question, ensure the status is Open. You cannot delete from a Posted Billing Run.
Right click within the Details tab and select Add Items to Batch
Scroll to, or select, the transaction you wish to remove
Right click and select Delete Record
Please note that by removing a billback invoice, the fees invoice relating to the removed billback invoice will NOT be affected. It is advised that the linked fees invoice should also be removed otherwise the client may receive a fee without receiving a billback invoice.