You did not say where he got the power from and where does the other cable go?
If he took it from a ceiling light, it only works if there is constant power there.
Pull that switch, if there are 2 black wires going to the switch you likely don't have constant power at the light.
If he took it from a ceiling light, it only works if there is constant power there.
Pull that switch, if there are 2 black wires going to the switch you likely don't have constant power at the light.