diff --git a/app/controllers/partners_controller.rb b/app/controllers/partners_controller.rb
index ded5d1cb..212ff3ca 100644
--- a/app/controllers/partners_controller.rb
+++ b/app/controllers/partners_controller.rb
@@ -100,7 +100,7 @@ def confirm
         @registration.deliver
         flash.now[:success] = "Your invitation has been confirmed. Your ticket should arrive shortly."
       else
-        flash.now[:error] = safe_join(
+        flash.now[:error] = ActionController::Base.helpers.safe_join(
           "It looks like there already is someone with your name and/or email registered for this event. ",
           view_context.mail_to(@event.contact_email, 'Contact us'),
           " if this is not correct."
diff --git a/app/controllers/sign_in_controller.rb b/app/controllers/sign_in_controller.rb
index d41afd1f..ea2ca8e4 100644
--- a/app/controllers/sign_in_controller.rb
+++ b/app/controllers/sign_in_controller.rb
@@ -28,7 +28,7 @@ def authenticate_partner_from_token!
     if partner
       sign_in partner, store: SimpleTokenAuthentication.sign_in_token
     else
-      flash[:error] = safe_join(
+      flash[:error] = ActionController::Base.helpers.safe_join(
         "Something went wrong. Make sure you click the link or copy the whole link (including parameters)! ",
         view_context.mail_to(@event.contact_email, 'Contact us'),
         " if the problem persists."