Hello, I have a problem while adding a new field to account.move.

This is my code in module.py file, but nothing happened

from odoo import models, fields, api

class AccountMove(models.Model):

_inherit = 'account.move

x_myField = fields.Float(0, store=False)

This is my code on view.xml

    <record id="_myField" model = "ir.ui.view">

      <field name="name">Name</field>

      <field name="model">account.move</field>

      <field name="inherit_id" ref = "account.view_invoice_tree" />

      <field name="arch" type = "xml"> 

<field name="company_id" position="after">

          <field name = "x_myField" />

        </field>

      </field>

    </record>

No matter what I try, it always returns the error:

Field "x_myField" does not exist in model "account.move"