Maybe, somebody could help... I am trying to get run a custom module with a new model inheriting from res_partner (example for keeping it short with only 1 additional field):

# -*- coding: utf-8 -*-
from odoo import models, fields
class FQ_Partner(models.Model):
    _name = 'fq.partner'
    _inherits = {'res.partner': 'partner_id'}
    partner_id = fields.Many2one('res.partner', required=True, ondelete='cascade')    
    fq_id = fields.Char('FQ Nr.', size=30)   

<?xml version="1.0" encoding="utf-8"?>
<odoo>
<record id="personal_information" model="ir.ui.view">
    <field name="name">Personal information page for contacts form</field>
    <field name="model">res.partner</field>
    <field name="inherit_id" ref="base.view_partner_form"/>
    <field name="priority">2</field>
    <field name="arch" type="xml">
        <data>
            <xpath expr="//page[@name='internal_notes']" position="after">
                <page name="personal_information_page"
                    string="Personal Information"
                    attrs="{'invisible': [('is_company','=',True)]}">
                    <group name="personal_information_group"/>
                </page>
            </xpath>
        </data>
    </field>
</record>
</odoo>

The new page is displayed, but if I insert my new field from my new model above, I can not access it (an error message appears that the field does not exist). If I change the model from res.partner to fq.partner (my new model), I do not get the error message any more when installing / upgrading my module, but the page does not get displayed any more. What am I doing wrong? How can I add my new data to this page keeping it displayed?