Transaction Throws "No tax agency defined for subsidiary: subsidiary null is not linked to nexus xx" upon Save

The error is caused by:
1. The tax code not having a tax agency assigned to it
2. The subsidiary not recognizing the nexus under the subsidiary record's Nexuses tab


Solution 1:

1. Navigate to to Setup > Accounting > Tax Code
2. Click Edit on the tax code involved.
3. Enter value in the Tax Agency field.
4. Save.


Solution 2:
1. Navigate to Setup > Company > Subsidiaries
2. Click Edit on the subsidiary involved.
3. If the nexus from the error message is missing in the Nexuses tab, add it.
4. If the nexus from the error message is under the Nexuses tab and NetSuite is not recognizing it, replace the value for that nexus with another nexus.
5. Save.
6. Edit the same subsidiary.
7. Replace the value for the nexus with the nexus in the error message.
8. Save.