In case you need to populate the field Total Net with the Total values, you can create a Calculate Sum rule on the Total Net Amount field with the below parameters:
- Condition: Apply if the Total Net Amount field is Empty.
- Summarize values of only the Total field. The Result field would be the Total Net Amount field.
With the above rule, the Total Net Amount field will be always populated with Total field value for invoices with unrecognized taxes and captured normally when taxes were recognized.