diff --git a/evapp/views.py b/evapp/views.py
index 9d93e33..c17031c 100644
--- a/evapp/views.py
+++ b/evapp/views.py
@@ -63,9 +63,10 @@ class EvaFormView(LoginRequiredMixin, CookieWizardView):
         data = super().get_all_cleaned_data()
         if not data['intern']:
                 print("intern employee detected")
-                if not data['email'].endswith('_ext'):
-                    print('added "_ext" to mail adress')
-                    data['email'] += '_ext'
+                (user, domain) = data['email'].split('@')
+                if not user.endswith('_ext'):
+                    print('add "_ext" to mail adress...')
+                    data['email'] = f'{user}_ext@{domain}'
 
         print("delete CHOICE FROM DATA")
         if 'choice' in data: