Over the last couple days, my iPhone 7 would restart by itself. Today, about 3-4 hours ago, the upper left corner was reading "searching". I'd restart it myself and the bars would reappear. About an hour ago, it read "no service." I can use my wifi but I know that my boss has called and texted me and it's stressing me out because he doesn't have apple. I've removed the SIM, checked for updates, restarted it, reset network settings, reset all setting... please help!! Wish there was a live chat option.