german is a language that is not nice to code. had to fix this quickly

app/controllers/volunteers_controller.rb

@@ -27,7 +27,7 @@ class VolunteersController < ApplicationController
     @volunteer.registrar = current_user
     authorize @volunteer
     if @volunteer.save
-      redirect_to @volunteer, make_notice
+      redirect_to @volunteer, notice: t('volunteer_created')
     else
       render :new
     end
@@ -40,13 +40,13 @@ class VolunteersController < ApplicationController
       redirect_to volunteers_path,
         notice: t('invite_sent', email: @volunteer.contact.primary_email)
     else
-      redirect_to @volunteer, make_notice
+      redirect_to @volunteer, notice: t('volunteer_updated')
     end
   end
 
   def destroy
     @volunteer.destroy
-    redirect_to volunteers_url, make_notice
+    redirect_to volunteers_url, notice: t('volunteer_destroyed')
   end
 
   private

config/locales/de.yml

@@ -186,7 +186,7 @@ de:
       relative: Verwante/r
       schedule: Zeitplan
       user: Benutzer/in
-      volunteer: Freiwillige/r
+      volunteer: Freiwillige/n
       volunteer_application: Freiwilligen Bewerbung
       volunteer_email: Bestätigungsmail
   add_language: Sprache hinzufügen
@@ -208,6 +208,7 @@ de:
   client_destroyed: Klient/in wurde erfolgreich gelöscht.
   client_updated: Klient/in wurde erfolgreich aktualisiert.
   clients: Klienten/innen
+  profile_updated: Der Login wurde erfolgreich geändert.
   contact_info: Kontakt Informationen
   contacts:
     fields: