If you have imported from Pay & Bill and they have been unable to balance the Nominal Lines that are sent across to Safe Financials, you must add the lines to correct for the imbalance whilst the batch sits within the Interface.
This can be done in the following way:
From the Toolbar click System Admin, External Interfaces, External Interface Controls
Click Journals
Populate new lines to make up the difference on the existing Journals, be sure to target the correct Nominal Accounts.