Why the sync error occurs
This error occurs when a bill that's been paid in Sage Intacct has been updated in Bill.com with an additional new line item and the update attempts to sync to Sage Intacct. A new line item on a bill cannot be synced to in Sage Intacct after the bill has been paid.
How to fix the sync error
Manually update the bill in Sage Intacct and contact Customer Support to request that the sync error be removed.