Hello,
It’s difficult to say without being able to view the site directly.
If the reCaptcha checkbox is not appearing:
Ensure that you’ve followed the installation instructions and that your domain is whitelisted.
If the reCaptcha checkbox is appearing but you are getting sent messages errors:
You can try removing the [recaptcha]
shortcode from the form and sending a test submission to narrow down where the issue lies. If you still receive the error then there may be a plugin conflict. You can install the Health Check & Troubleshooting plugin which will allow you to easily and safely disable plugins. You’ll need to disable everything excerpt Contact Form 7 and this plugin then submit a test to the form to see if it sends. If it is successful you will need to enable each plugin one by one, testing along the way, to narrow down the offending plugin.
Hopefully the above finds you well. Should you have any questions, comments, concerns please reply back to this thread and we can assist you further.