Then, you didn't set it up properly.
Delete the OBiTALK device off of your OBiTALK dashboard. Unplug the device power and Ethernet cords. Plug in just the power cord. Let it boot up, then pick up the phone and press ***8 then 1 to confirm, to restore the device to factory defaults. After it gyrates and reboots, then unplug it again. Plug both power and Ethernet cords back in and wait. After it's done rebooting...
Add the device back to the OBiTALK web portal. After it is added back and it reboots once or twice more, then set up SP1 with Google Voice and pay close attention to the account it is asking you to use.