Avatax taxes are not applied to the order
1.Visit > Phone Orders > Settings > Common and turn on “Switch Customer”
2. Adjust Avatax settings, set option “Cart Calculation” = “Force full tax rate calculation”
3. AvaTax plugin doesn’t work in admin context. So you should edit files in this plugin a bit.
Comment lines 97-99 in the file includes/class-wc-avatax-tax-handler.php