Fix copy&paste error.

ticdesk_events/views.py

@@ -102,8 +102,8 @@ def register_event(request, cn):
                     guardian.mobile == register_form.cleaned_data['guardian_mobile']
                 ):
                     # Either mail or mobile matches - update both and link
-                    guardian.mail = register_form.cleaned_data['guardian_mail'] or
-                    guardian.mobile = register_form.cleaned_data['guardian_mobile']):
+                    guardian.mail = register_form.cleaned_data['guardian_mail']
+                    guardian.mobile = register_form.cleaned_data['guardian_mobile']
                     guardian.save()
 
                     if guardian.dn not in current_person.guardians: