function always_create_new_contacts( $contact_id, $update_data, $user_id, $form_id ) {

    if ( $form_id == 22 || $form_id == 29 || $form_id == 30 || $form_id == 28 ) {

        $contact_id = false;

    }

    return $contact_id;

}

add_filter( 'wpf_formidable_pre_submission_contact_id', 'always_create_new_contacts', 10, 4 );