Redirect on Ninja Forms not working

Hello,

We have a Contact Form button on the Details Page. We set Redirect in Email & Actions Ninja Form with URL {wp:post_url}/?website=websiteurl. Supposedly if I have filled out the form and clicked submit then I will be directed to the URL that I have set in the Redirect settings and a word appears.

But what I noticed, when I have filled out the form and then clicked submit, there’s a success message and it displayed the detail page in Lightbox instead of the URL I had set.

The way it works is supposed to be when I fill out the form and then click submit, I will be directed to the URL that I set in Redirect and then bring up a word.
Can you see this problem and tell us the solution?

SS Pictures:
Settings Redirect: https://www.awesomescreenshot.com/image/9321979?key=c728b134486346392f4e44517b9b3166
Result: https://www.awesomescreenshot.com/image/9322017?key=830ac93d9255ab0762dfcc9911da908d
https://www.awesomescreenshot.com/image/9322039?key=d66215467f6375e72aed109b3ba2d285

Thank you

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