This error message can be displayed in such cases:
- some form fields are not filled;
- security nonce validation failed;
- Google reCaptcha is enabled in the plugin settings, but incorrect or outdated Google reCaptcha developper keys are used;
- Google reCAPTCHA is enabled in the plugin settings, but we could not get a response from google servers to check the captcha;
- Google reCAPTCHA is enabled in plugin settings, but captcha verification failed;
All fields are filled and Re-captcha is OFF
What is “security nonce validation failed”, could you explain, please?
This means that the verification of sequrity nonces has failed. Nonces are used to protect forms from certain types of misuse, malicious or otherwise.
Thank you for the answers,
I think it’s not supported on multi-sites.