Not working for me on Virtuemart "ask a question about this product"

Hi,
I have the latest version of ECC+ (2-5-7), and it is working fine for the contact form as well as product checkout page, but it's not working for the "ask a question about this product" popup.
I use a Virtuemart template and I have tested with another one, but it's not working for either.
Example page with the problem:
Sapphire Gemstone Online Website
I tried all available captcha modes, encrypted and not, various settings...
It's just not working for me.
Any suggestion?
Kind Regards,
Mat

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