Help wanted

Can any one tell me if you can lock the keypad on a v3x. I do not want to
lock the phone with a code. My phone is turning its self off in my pocket. I
have been in touch with three3 and they tell me I need to lock the keypad.
There is nothing in the manual that three3 supply that says about keypad
lock only phone lock.
The buttons on the side are not for turning the phone off so does it mean
the phone is faulty.
The phoe is being used for emergency calls between hospital and me.
Thankyou