Why the Sync Error occurs
This error occurs when you are setting up your sync with Oracle NetSuite in Bill.com, but SuiteTax is enabled in Oracle NetSuite.
How to Fix the Sync Error
We do not currently support syncing with Oracle NetSuite if SuiteTax is enabled in Oracle NetSuite and advanced receivables is also enabled in Bill.com.
In order to sync, you will need to disable SuiteTax in Oracle NetSuite, or disable advanced receivables in Bill.com.