Traceback (most recent call last):
  File "/home/odoo/src/odoo/13.0/odoo/addons/base/models/ir_http.py", line 229, in _dispatch
    result = request.dispatch()
  File "/home/odoo/src/odoo/13.0/odoo/http.py", line 803, in dispatch
    r = self._call_function(**self.params)
  File "/home/odoo/src/odoo/13.0/odoo/http.py", line 345, in _call_function
    return checked_call(self.db, *args, **kwargs)
  File "/home/odoo/src/odoo/13.0/odoo/service/model.py", line 93, in wrapper
    return f(dbname, *args, **kwargs)
  File "/home/odoo/src/odoo/13.0/odoo/http.py", line 338, in checked_call
    result = self.endpoint(*a, **kw)
  File "/home/odoo/src/odoo/13.0/odoo/http.py", line 909, in __call__
    return self.method(*args, **kw)
  File "/home/odoo/src/odoo/13.0/odoo/http.py", line 510, in response_wrap
    response = f(*args, **kw)
  File "/home/odoo/src/odoo/13.0/addons/website_event_sale/controllers/main.py", line 40, in registration_confirm
    cart_values = order.with_context(event_ticket_id=ticket.id, fixed_price=True)._cart_update(product_id=ticket.product_id.id, add_qty=1, registration_data=[registration])
  File "/home/odoo/src/odoo/13.0/addons/website_event_sale/models/sale_order.py", line 82, in _cart_update
    values.update(super(SaleOrder, self)._cart_update(product_id, line_id, add_qty, set_qty, **kwargs))
  File "/home/odoo/src/custom/private/openerp_enterprise/models/openerp_enterprise.py", line 3491, in _cart_update
    add_qty=add_qty, set_qty=set_qty, **kwargs)
  File "/home/odoo/src/odoo/13.0/addons/website_sale/models/sale_order.py", line 185, in _cart_update
    raise UserError(_("The given combination does not exist therefore it cannot be added to cart."))
odoo.exceptions.UserError: ('The given combination does not exist therefore it cannot be added to cart.', '')