Google Re Captcha is not working

Hello, I have enabled Google recaptcha on all registration form using this plugin

Re captcha on all forms work correctly except in Registration form I get “ERROR for site owner: Invalid site key”

As you can see here:
Register Page>>> https://www.peramovies.club/register-2/
Login Page: https://www.peramovies.club/login-3/
Password reset Page: https://www.peramovies.club/password-reset/

May I know why?

The page I need help with: [log in to see the link]