Turn camera off and on again?!?

Hello

I have a Sony Camera Cyber-Shot DSC-H90.

It was working perfectly but I turned it on and after setting all the settings, I turned my camera on and after about 3 seconds the lens shut closed and the camera gave me an instruction saying the following: "Turn camera off and on again"

Can someone please tell me what to do? And what could perhaps be the problem that is causing this?

REGARDS

SAFEER AHMED