Lighting not work please help!!

Hey! I am new to blender, as today I am following the tutorial by blenderwiz

everything goes fine until I do the final rendering, I found the lamp is not working


Can anyone please have a look please?

Attachments

randomcube.blend (1.96 MB)

You should have added a plane as your lamp.and also asky.
randomcube.blend (1.78 MB)

wow it works! Thank you!!