Contact Form 7 Redirect using functions.php file.

contact-form-7-redirect.php

add_action( 'wp_footer', 'bsd_cf7_redirect_wp_footer' );
 
function bsd_cf7_redirect_wp_footer() {
?>
<script type="text/javascript">
document.addEventListener( 'wpcf7mailsent', function( event ) {
    // here 4423 is the id of the form, replace it with your form id
    if ( '4423' == event.detail.contactFormId ) {
        location = 'https://secova.com/thank-you-demo';
    }
    // here 4513 is the id of the form, replace it with your form id
    if ( '4513' == event.detail.contactFormId ) {
        location = 'https://secova.com/thank-you-contact';
    }
}, false );
</script>
<?php
}