Issues with CAPTCHA

Hi there

I am having issues with the CAPTCHA part of MailPoet plugin in WordPress. If I activate ‘Built-in CAPTCHA (default)’ in the plugin’s settings then as a newsletter subscriber I am asked to type in the letters and numbers I see to confirm that I am not a bot. But I never succeeded to go past this hurdle. It always tells me that my input was not correct.
So next I tried the plugin’s option ‘Google reCAPTCHA v2’ and provided the Google reCAPTCHA keys for v2 with the Google seetings ‘Invisible’ for v2. Despite this ‘Invisible’ the MailPoet newsletter sign-up form prompts the user for a checkbox confirming that I am no robot. I am surprised to see this checkbox because this is set to ‘Invisible’ in Google… but never the less I check the box and submit the form. But I get an error messaging saying that I have to wait 1h, 2h, 4h, 8h, etc. until I can try again. So I set up a new reCAPTACH v2 in Google. This time not setting it to ‘Invisible’ but instead to ‘Checkbox’. I update the reCAPTCHA keys in the MailPoet module in WordPress. If I now try to sign up to the newsletter I am again shown the checkbox to confirm I am not a bot and again I can not submit the form and I am asked to wait 1h, 2h, 4h, etc. to retry.

Do you have an idea what could be wrong here? I have tried this with Chrome on Windows, Android, and iPad OS.

Thanks & regards,
Flix

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