Invoice Error: Cannot delete /update line items. At least one line item must exist for each tax amount with the same matter and type
When editing the matter in your invoice, the error shows: Cannot delete /update line items. At least one line item must exist for each tax amount with the same matter and type. This caused by an existing tax item, referenced on the previous matter in the invoice.
Solution: Go to the "Taxes & Discounts" page and Delete the tax item.
Then return to the Line Items page and delete or update the line item.