"Subscribe without comment" not working

Hello, I use the latest WP-version (4.2.1) and the latest plugin version (150422). Unfortunately when I click on “Subscribe without comment” a 404 message appears. The link is like this: [domain]/comment-subscriptions?srp=62838&srk=&sra=s

Any ideas?

https://wordpress.org/plugins/subscribe-to-comments-reloaded/