$tracking_item = array();
$tracking_itemst = get_post_meta( $order_id, '_wc_shipment_tracking_items', true );
if ( is_array( $tracking_itemst ) ) {
if ( $formatted ) {
foreach( $tracking_itemst as &$item ) {
$formatted_item = $this->get_formatted_tracking_item( $order_id, $item );
$item = array_merge( $item, $formatted_item );
}
}
}
$tracking_provider = strtolower($shipment->selected_rate->carrier);
$tracking_item[ 'tracking_provider' ] = wc_clean( $tracking_provider );
$tracking_item[ 'custom_tracking_provider' ] = wc_clean( $args[ 'custom_tracking_provider' ] );
$tracking_item[ 'custom_tracking_link' ] = wc_clean( $args[ 'custom_tracking_link' ] );
$tracking_item[ 'tracking_number' ] = wc_clean( $shipment->tracking_code );
$tracking_item[ 'date_shipped' ] = wc_clean( $date );
$tracking_items = $tracking_itemst;
$tracking_items[] = $tracking_item;
update_post_meta( $order_id, '_wc_shipment_tracking_items', $tracking_items );