fix

djangocms_forms/cms_plugins.py

@@ -108,6 +108,7 @@ class FormPlugin(CMSPluginBase):
             form_slug = "form-%d" % instance.plugin_reference.id
         except:
             form_slug = ""
+
         submission_instance = instance
 
         if request.session.get(form_slug, False):

djangocms_forms/forms.py

@@ -259,7 +259,7 @@ class FormBuilder(forms.Form):
     def save_to_db(self, form_data, request, referrer):
         user = request.user if request.user.is_authenticated() else None
         # Если есть сессия для этой формы, то сохраняем в неё.
-        form_slug = "form-%d" % self.form_definition.plugin_reference.id
+        form_slug = "form-%d" % (self.form_definition.plugin_reference.id or self.form_definition.id)
         if request.session.get(form_slug, False):
             try:
                 form_instance = FormSubmission.objects.get(id=request.session.get(form_slug, False))