Captcha mismatch, Please try again.

I fill in all the fields Nina Forms, activate reCAPTCHA, but when I click the send button Nina Forms return error “Captcha mismatch, Please try again.”. reCAPTCHA Site Key and reCAPTCHA Secret Key filled. What could be wrong?

https://ww.wp.xz.cn/plugins/ninja-forms-recaptcha-field/