Buonasera a tutti,
ho aggiornato i moduli della versione 12 dei contratti ricorrenti con i moduli della community italiana, ma ora quando cerco di generare una fattura da un contratto ricorrente, sempre funzionato, ora mi da l'errore seguente:

Traceback (most recent call last):
  File "C:\Program Files (x86)\Odoo 12.0\server\odoo\http.py", line 656, in _handle_exception
    return super(JsonRequest, self)._handle_exception(exception)
  File "C:\Program Files (x86)\Odoo 12.0\server\odoo\http.py", line 314, in _handle_exception
    raise pycompat.reraise(type(exception), exception, sys.exc_info()[2])
  File "C:\Program Files (x86)\Odoo 12.0\server\odoo\tools\pycompat.py", line 87, in reraise
    raise value
  File "C:\Program Files (x86)\Odoo 12.0\server\odoo\http.py", line 698, in dispatch
    result = self._call_function(**self.params)
  File "C:\Program Files (x86)\Odoo 12.0\server\odoo\http.py", line 346, in _call_function
    return checked_call(self.db, *args, **kwargs)
  File "C:\Program Files (x86)\Odoo 12.0\server\odoo\service\model.py", line 97, in wrapper
    return f(dbname, *args, **kwargs)
  File "C:\Program Files (x86)\Odoo 12.0\server\odoo\http.py", line 339, in checked_call
    result = self.endpoint(*a, **kw)
  File "C:\Program Files (x86)\Odoo 12.0\server\odoo\http.py", line 941, in __call__
    return self.method(*args, **kw)
  File "C:\Program Files (x86)\Odoo 12.0\server\odoo\http.py", line 519, in response_wrap
    response = f(*args, **kw)
  File "c:\program files (x86)\odoo 12.0\server\odoo\addons\web\controllers\main.py", line 966, in call_button
    action = self._call_kw(model, method, args, {})
  File "c:\program files (x86)\odoo 12.0\server\odoo\addons\web\controllers\main.py", line 954, in _call_kw
    return call_kw(request.env[model], method, args, kwargs)
  File "C:\Program Files (x86)\Odoo 12.0\server\odoo\api.py", line 759, in call_kw
    return _call_kw_multi(method, model, args, kwargs)
  File "C:\Program Files (x86)\Odoo 12.0\server\odoo\api.py", line 746, in _call_kw_multi
    result = method(recs, *args, **kwargs)
  File "c:\program files (x86)\odoo 12.0\server\odoo\addons\contract\wizards\contract_manually_create_invoice.py", line 58, in create_invoice
    invoices |= contract.recurring_create_invoice()
  File "C:\Program Files (x86)\Odoo 12.0\server\odoo\models.py", line 5065, in __or__
    return self.union(other)
  File "C:\Program Files (x86)\Odoo 12.0\server\odoo\models.py", line 5074, in union
    raise TypeError("Mixing apples and oranges: %s.union(%s)" % (self, arg))
TypeError: Mixing apples and oranges: account.invoice().union(None)

Qualcuno riesce a farmi capire cosa ho dimenticato di settare?

Grazie,
Simone