How to solve: reCAPTCHA response token is empty?

Hello,

My forms are not working correctly. They are always showing SPAM error message even when it’s not spam. I know it comes from the fact that reCAPTCHA response token is empty, but I can’t find any solution online for this problem. I know it can be from an ill-designed theme (as seen in this topic: https://contactform7.com/faq-about-recaptcha-v3/#response-token-is-empty) but how do I solve this?

Thank you

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