Restarting and heat

[Mom_and_Teacher]

Recenty my droid turbo 2 has been randomly restarting. At first I thought I accidentally hit the power key, but this has happened across two days and with a charge in between. After it shut down, I noticed the phone was hot to touch. Is the auto off due to over heating, and if so what can I do to keep it from overheating as easily? I just had it in my hand for a walk on an 80 degree day when it turned off today. I do not have a cover on the phone either.