I am in an administrator role and I am unable to change the tax code on an existing invoice from avatax to non-taxable. why is this ?

AI generated answer (using internal Slack threads):

In NetSuite, the tax code on an invoice is determined by several factors, including the nexus, the ship-to address, and the tax setup of the company. If you are unable to change the tax code on an existing invoice from Avatax to non-taxable, it could be due to the following reasons: 1. Nexus and Ship-to Address: The tax code is determined by the nexus and the ship-to address. If the ship-to address is in a state where you have a nexus, the tax code will be determined by the nexus, not the default tax code. If the ship-to address is in a state where you don't have a nexus, the default tax code will be used. 2. Tax Setup: The default tax code is set in the SETUP TAXES page. If the default tax code is set to Avatax, all new invoices will use this tax code. To change the default tax code to non-taxable, you need to change it in the SETUP TAXES page. 3. Closed Period: If the invoice is in a closed period, you may not be able to change the tax code. Even if "Allow non-gl changes" is checked for the period, changing the tax code could be seen as a GL change and therefore disallowed. 4. Tax Calculation Engine: If you are using a tax calculation engine like AVALARA, you may not be able to override the tax details on a transaction. If you check the Tax Override checkbox to get the tax to be zero, you may get an error from the tax calculation engine. 5. Per-Line Taxes on Transactions: If the "PER-LINE TAXES ON TRANSACTIONS" option is checked in the SETUP TAXES page, the tax code will be set for each line item on the invoice. If you uncheck this option, the tax code will be set on the header of the transaction body, not for each line item. Please note that changing the tax code on an existing invoice will not affect the tax calculation for that invoice. The tax code is determined at the time the transaction is created. If you want to change the tax code for an existing invoice, you need to create a new invoice with the correct tax code. ****** Disclaimer: This response was generated by an artificial intelligence assistant based on previous conversations from multiple Slack channels, and may contain inaccuracies or mistakes. ******