Java Scipt Error, all links not working anymore

Hi

Somehow I got a javascript error

Uncaught TypeError: Cannot read property ‘send’ of undefined
at HTMLAnchorElement.<anonymous> (wp-post-modal-public.js?ver=1.0.0:312)
at HTMLBodyElement.dispatch (jquery.js?ver=1.12.4:3)
at HTMLBodyElement.r.handle (jquery.js?ver=1.12.4:3)

Especially, when I have on this page in the bottom: https://www.see-samui.com/samui-fuehlen/ a tickbox, where it should open another page with the terms & conditions.

Anything I can do?

Regards,
Simon

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