My cell phone shut off randomly, what gives?

I have had the LG enV3 from Verizon for about 3 months now. For the past few weeks it has been shutting off randomly, one or two times per day. The thing is, it only happens when it sits in my pocket during work. I have been sitting it on my desk for the past two days and it has not shut off yet and it never does it on the weekend while it mostly sits on my coffee table.

You’re probably thinking that I’m hitting the Power button on accident while it’s in my pocket. This can’t be, because the outside buttons on the phone are locked unless you press the OK button twice. And I highly doubt that I am accidently pressing it twice, then holding the Power button until it shuts off. Also, I have never felt it vibrate when it shuts down. I feel every vibrate of text messages and phone calls, but I won’t know it shut off until I happen to look at my phone and realize it’s been off for a couple hours.

This is a weird situation, but what could possibly be going on? I’ve been thinking about calling Verizon. What do you think they could accomplish for me in regards to this situation?