Always do your best to contact the customer when you arrive.
If you are absolutely unable to reach the customer or if they are unavailable, let Gourmet Runner Dispatcher know about it by sending a text message.
1) Once you sent a text message to the Dispatcher wait for 10-15 minutes.
Try to contact customer again during that time.
2) After 15 minutes wait is over ask the Dispatcher about further instructions.
In most cases you can keep the food for yourself, but sometimes restaurants ask to return for additional payment