I'm getting an "unknown field" error, eventhough the model does have the fields. 
What am i doing wrong?



Traceback (most recent call last):
  File "/Users/jgs/jgs/Coding/Projects/odoo15/odoo/odoo/http.py", line 643, in _handle_exception
    return super(JsonRequest, self)._handle_exception(exception)
  File "/Users/jgs/jgs/Coding/Projects/odoo15/odoo/odoo/http.py", line 301, in _handle_exception
    raise exception.with_traceback(None) from new_cause
odoo.tools.convert.ParseError: while parsing /Users/jgs/jgs/Coding/Projects/odoo15/odoo/addons/rectanglemaps/views/create_order_views.xml:4
Fehler bei der Validierung der Ansicht nahe:

                    
                        
                        
                    
                

Unbekanntes Feld "event.registration.event_booth_id" in domain of  ([('event_id', '=', event_id), ('event_booth_id.halle_id', '=', halle_id)])

View error context:
{'file': '/Users/jgs/jgs/Coding/Projects/odoo15/odoo/addons/rectanglemaps/views/create_order_views.xml',
 'line': 8,
 'name': 'rectanglemaps.order.wizard.form',
 'view': ir.ui.view(2490,),
 'view.model': 'rectanglemaps.order.wizard',
 'view.parent': ir.ui.view(),
 'xmlid': 'rectanglemaps_create_order_view_form'}

This is my code:

<record id="rectanglemaps_create_order_view_form" model="ir.ui.view">
    <field name="name">rectanglemaps.order.wizard.formfield>
    <field name="model">rectanglemaps.order.wizardfield>
    <field name="arch" type="xml">
        <form>
            <group>
                <group>
                    <field name="event_id" readonly="1"/>
                group>
                <group>
                    <field name="event_registration_ids"
                           widget="many2many_tags"
                           domain="[('event_id', '=', event_id), ('event_booth_id.halle_id', '=', halle_id)]"/>
                    <field name="plan" widget="image"/>
                group>
            group>
            <footer>
                <button string="Anlegen" class="btn-primary" special="save"/>
                <button string="Abbrechen" class="btn-secondary" special="cancel"/>
            footer>
        form>
    field>
record>

And this is the model:

# -*- coding: utf-8 -*-
from odoo import models, fields, api
from . import prepare_engine as rectanglemaps_engine


class EventBoothRegistration(models.Model):
    _inherit = 'event.booth.registration'

    plan = fields.Binary(string='Plan', attachment=True)

and EventBooth

class EventBooth(models.Model):
    _inherit = 'event.booth'

    name = fields.Char(string='Name', compute='_compute_name')
    display_name = fields.Char(string="Anzeigename", compute='_compute_display_name', inverse='_inverse_display_name',  store=True)

    # Verbundene Halle
    halle_id = fields.Many2one('rectanglemaps.halle', string='Halle')

thank you for you patience!