It is necessary to detail the location of your tickets at the time of publishing your listing. In order to do so, you must: 

Locate the event you want to list your tickets for on StubHub, and then press the “Sell” button.
In the sale process you’ll find the seating map created by StubHub for the event.
You must then go to the “Location” section. To increase your chances of selling, we recommend that you indicate the exact information regarding Block and Row.
If you want to add any additional information that may be considered important to the buyer, you may indicate it this in the “Restrictions” section.