Function VI_WOOCOMMERCE_ORDERS_TRACKING_DATA::set_tracking not found

Dear Sir,

We are using free version of Woo Orders Tracking.

We are trying to develop a tracking update function. We want to use the function

VI_WOOCOMMERCE_ORDERS_TRACKING_DATA::set_tracking( $order_id, $tracking_number, $carrier_slug, $item_id, $quantity_index, $add_to_service, $add_to_paypal, $send_email, $send_sms);

as mentioned in your documentation.

However, we getting error that this function is not found.

Do we need a premium version if we want to call this function or is there something we need to do in order that this function can be called.

Thanks

Sanjay