reCAPTCHA will not show up

Hello and thank you very much for this awesome WordPress plugin!

Im using TML now for a long time and now Im getting more and more Spam Users. So I decided to Enable reCAPTCHA. I have inserted the public and private key, but nothing at all changed on my Login site: http://www.ps4source.de/registrieren/

If you try to register now, it will sent you an error to enter the Captcha Code. But as you can see there is no Captcha.

Could you please help me?

https://wordpress.org/plugins/theme-my-login/