Form works on home page but not subpages

This is a really weird issue. We have a global Formiddable Form that opens up in a modal on every page of our site. It’s the “Book Appointment” button in the main navigation.

The form works perfectly on the home page, it submits and goes to the Thank You page.

But on all subpages, when that exact same form is submitted, it reloads the same page and does not submit the form.

I’m not seeing the problem. As far as I know there is nothing different about the home page and subpages as far as different plugins/scripts being used. Everything is identical. There are no JS errors or errors in the server logs. But clearly the form is behaving differently.

Any ideas?

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