Are you mapping this file in the __init__.py file like this?

You need import file or folder to __init__ file.

well the problem here is that the field is added in the model check 

i created  a simple module in odoo 17 i want to add custom field to company view  

<odoo>
    <record id="view_res_company_form_unique_view" model="ir.ui.view">
        <field name="name">res.company.form.inherit.unique.view</field>
        <field name="model">res.company</field>
        <field name="inherit_id" ref="base.view_company_form"/>
        <field name="arch" type="xml">
            <xpath expr="//field[@name='company_registry']" position="after">
                <field name="custom_field"/>
            </xpath>
        </field>
    </record>
</odoo>

Manifest 

# -*- coding: utf-8 -*-
{
    'name': "company_details",

    'summary': "Short (1 phrase/line) summary of the module's purpose",

    'description': """
Long description of module's purpose
    """,

    'author': "My Company",
    'website': "https://www.yourcompany.com",

    # Categories can be used to filter modules in modules listing
    # Check https://github.com/odoo/odoo/blob/15.0/odoo/addons/base/data/ir_module_category_data.xml
    # for the full list
    'category': 'Uncategorized',
    'version': '0.1',

    # any module necessary for this one to work correctly
    'depends': ['base'],

    # always loaded
    'data': [
        # 'security/ir.model.access.csv',
        'views/res_company_views.xml',
    ],
}

class ResCompany(models.Model):
    _inherit = 'res.company'

    custom_field = fields.Char(string="Custom Field")

You might have added a field custom_field in xml view file, but it is not defined in the corresponding model (res.company).

Solution: Define the field in the res.company model.

from odoo import fields, models 

class ResCompany(models.Model):

 _inherit = 'res.company' 

custom_field = fields.Char(string="Custom Field")