Hello, I am trying to add a discount on the invoice total by adding a new field and subtracting one percent out of the total, so that I can have an "Amount Due" of the : total-discount. Here is my code:

from odoo import fields, models, api

class AccountInvoiceInherit(models.Model):
    _inherit = 'account.move'

    one_percent_amount = fields.Float('1% Discount',compute='_compute_one_percent')
    amount_residual = fields.Monetary(compute='_compute_amount_due', store=True)

    @api.depends('amount_total')
    def _compute_one_percent(self):
        for record in self:
            record.one_percent_amount = (record.amount_untaxed * 0.1)

    @api.depends('amount_untaxed', 'one_percent_amount')
    def _compute_amount_due(self):
        for record in self:
            record.amount_residual = record.amount_untaxed - record.one_percent_amount

View File:

xml version="1.0" encoding="utf-8"?>

        
        id="account_invoice_form" model="ir.ui.view">
            name="name">account.invoice.form
            name="model">account.move
            name="inherit_id" ref="account.view_move_form"/>
            name="arch" type="xml">
                expr="//field[@name='amount_total']" position="after">
                    name="one_percent_amount"/>
                
            
        

How to solve it? The code is not giving any error, but the deduction is not occuring