Who I have the same questioned this topic

S9 started just randomly turning off and restarting by itself over past 2 weeks. I've cleared cache partition, deleted any apps that I had downloaded over last 2 weeks and started back up in safe mode. It still continues to happen up to a dozen times a day. Shuts off during a call, attempting to text, taking a picture or opening an app, making the use of this phone pretty worthless at this time.