Hi there,
Go to
Extensions -> Plugins and find this plugin called
Captcha - ReCaptcha and click on it.
After that choose version as 2.0, not 1.0
There are 2 other boxes which are
site and
secret key which value you can get from
https://www.google.com/recaptcha. After getting the value enter it on those fields and save it.
Now go to
SP Page Builder page -> contact form add-on and elect
Captcha Type as
Google reCaptcha
Let me know if it’s working for you.
Thanks.