Why does my iPhone XR keep restarting on itself?

For about a couple of days now, my phone will not stop restarting itself whenever I go near the home bar/button thing and it's getting worse as the days come on. I've looked it up and said to do a complete hard reset on my phone but I have no way of backing up the photos and everything I have on it. I did capture a video of this happening earlier today, and I even had the on-screen dot for the home bar/button and that does the exact same thing. Should I go to the original carrier of the phone to see if they can do something about it?