Before activating, please ensure that you have the $5 Value Bundle from MetroPCS. This plan includes the Conditional Call Forwarding feature which allows TrapCall to work on your device.
Once this is enabled and you already have a paid account, please dial **004*5303036234# and press Call. Don't forget to include the * and # symbols when dialing. You should see Setting Activation Succeeded. Your phone is now activated.