Contact Form 7 Redirect to Undefined

Im having an issue where my contact form 7 is redirecting to a 404/undefined page after submission. The thank you message appears for a second so the submissions are going through, but the redirect happens directly after that. I created a test form here to showcase the issue https://staging-pifeqidu.kinsta.cloud/testing/ The form is out of the box, my plugin is up to date and I flushed my permalinks.

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