How to include field groups in email sent after form submission

OK, so I have a form with like 8 field groups with 3-4 sub-fields in each.

I'd like to send an email after form submission to admin including all those groups and sub-fields values and labels.

But I can't do that. I can include regular fields values (value 1 and 2 in my code), Value 3 is what gives me trouble.

This is what I'm trying to use:

add_action( 'rwmb_frontend_after_process', function( $config, $post_id ) {
    if ( 'application_form' === $config['id'] ) {
            $value1 = empty( $_POST['text_8qziiie3rt6'] ) ? null : $_POST['text_8qziiie3rt6'];
            $value2 = empty( $_POST['text_text'] ) ? null : $_POST['text_text'];
            $value3 = $group = rwmb_meta( 'contact', '', $post_id );
                    $t1 = $group['contact_1'];
                    $t2 = $group['contact_2'];
            $to = '[email protected]';
            $subject = 'New application';
            $body = '<div class="mail-body" style="color:#ccc;">Your application details: ' . '' . '<div>' . 'Text 1:' . $value1 . '</div>' . '<div>' . 'Text 2:' . $value2 . '</div>' . '<div>' . 'Text 3:' . $value3 . '</div>' . 'This is it!</div>';
            $headers = array( 'Content-Type: text/html; charset=UTF-8' );
            
            wp_mail( $to, $subject, $body, $headers );

            wp_safe_redirect( 'thank-you' );
        
        die;
    }
}, 10, 2 );

Also, is there a way to include all of those fields at once, like the entire form with the fields' values and names? I got around 30 fields....

Thank you for all your help, you're awesome.