Prevent Entries from being saved

// fire the action for all forms
add_action( 'gform_after_submission', 'my_remove_entries' ), 10, 2 );

// to only fire the action for a specific form, replace the "2" with the ID of your form
// add_action( 'gform_post_submission_2', 'my_remove_entries', 10, 2 );

function my_remove_entries( $entry, $form ) {

    global $wpdb;

    $lead_id                = $entry['id'];
    $lead_table             = RGFormsModel::get_lead_table_name();
    $lead_notes_table       = RGFormsModel::get_lead_notes_table_name();
    $lead_detail_table      = RGFormsModel::get_lead_details_table_name();
    $lead_detail_long_table = RGFormsModel::get_lead_details_long_table_name();

    // Delete from detail long
    $sql = $wpdb->prepare( " DELETE FROM $lead_detail_long_table
                            WHERE lead_detail_id IN(
                            SELECT id FROM $lead_detail_table WHERE lead_id=%d
                            )", $lead_id );
    $wpdb->query( $sql );

    // Delete from lead details
    $sql = $wpdb->prepare( "DELETE FROM $lead_detail_table WHERE lead_id=%d", $lead_id );
    $wpdb->query( $sql );

    // Delete from lead notes
    $sql = $wpdb->prepare( "DELETE FROM $lead_notes_table WHERE lead_id=%d", $lead_id );
    $wpdb->query( $sql );

    // Delete from lead
    $sql = $wpdb->prepare( "DELETE FROM $lead_table WHERE id=%d", $lead_id );
    $wpdb->query( $sql );

}