Report your xbox or playstation stolen to the company, the console will be internet locked till you report back & tell them it has been returned to you. Won't do a whole lot but if its a xb1 or ps4, they will be screwed since many games require online. Even if you don't have the serial on hand, xbox or playstation should know it anyway. Your console is registered to your gt, the company gets the serial through activation of the console.