You can go to contact form -> edit form ->(look in the top there is some tab form/mail/messages/Additional setting/) go to additional setting -> copy paste this line
on_sent_ok:”location.replace(‘https://www.example.com’);”
set your Redirect line on https://www.example.com save that.
And then in that form submit will take you to your expected link and form will be submitted. You can try this.
