If you have a device that's using it already, you could look at the setup for that device. If you don't, or still can't find it, and it's not the factory default setting (you can find the manual online) you may have to reset to the factory default, set a new password that you can keep track of, and reconfigure all your devices.
If you have a device that's using it already, you could look at the setup for that device. If you don't, or still can't find it, and it's not the factory default setting (you can find the manual online) you may have to reset to the factory default, set a new password that you can keep track of, and reconfigure all your devices.