hcaptcha not a required field in brevo form

I integrated hcaptcha in my brevo (sendinblue) form to sign up to the list, and it is displayed and works, but people can sign up without solving the captcha.

this is the code in the form:

<script src="https://js.hcaptcha.com/1/api.js"></script>

<div class="signup">
<p class="sib-email-area">
    e-mail address*
    <input type="email" class="sib-email-area" name="email" required="required">
</p>
<p><input type="checkbox" name="terms" required="required"> I accept the <a href="https://www.wildmoon.eu/privacy-policy/">privacy policy</a> </p>
<p><div class="h-captcha" data-sitekey="sitekey"></div>
</p>
<p>
    <input type="submit" class="sib-default-btn" value="sign up">
</p>
</div>

how do I make it that it’s required? I didn’t find info on that anywhere.

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