Camera issue with Latitude E5430

I got this laptop as a gift. It is running Win 10 upgraded from Win7.  

I was told that this laptop had no camera issues before.

I'm afraid to shut down my laptop because any kind of shut down/ restart may make my camera dysfunctional. I've been hibernating it for too long. And I also had to disable Windows update to prevent restarting.

At first, I did a simple restart to fix it. Sometimes it works, sometimes it doesn't.

It sounds like a random charm.

I do nothing special to fix it, and depend on pure luck to have it work.

My work is dependent on the video and the sound and I'm desperate for a definite solution.

Many helps for the help!