Ensure you have turned on your android device manager:
.Open Google Settings app.
.Tap on Security.
.Under Android Device Manager,switch on 'Remotely locate this device' and 'Allow remote lock and erase' to enable this function.
Turn on the location access on your Android device.
Check to ensure that Android Device Manager can locate your smartphone.
By following the above mentioned steps,Google Android Device Manager will find your smartphone.
Tapping on this button,your Android will ring.