Group checkbox selection does not work on front end

Hello!

I set up a form with 2 mailchimp interet groups settings: one hidden and pre-selected, that works normally to assign a group to senders, and one visibile and not pre-selected, for an optional newsletter subscription.

The last one does not work on front-end: isn’t possibile to select the checkbox, and if I set it up as pre-selected (not GDPR compliant) the checkbox is impossible to de-select.

The form works normally apart that

Thanks for your help!

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