The iPhone 8 and iPhone 8 Plus are smartphones designed, developed, and marketed by Apple Inc. They are the 11th generation of the iPhone. They were released on September 22, 2017, succeeding iPhone 7 and iPhone 7 Plus. The iPhone 8 and iPhone 8 Plus were discontinued by Apple on April 15, 2020, with the release of the second-generation iPhone SE.
IPhone 8 has multiple function issues, the phone automatically switches off and on, and sometimes it's dead and doesn't start unless is rebooted, it could be a hardware problem, according to a review by shashi758 at mouthshut.com
"I purchased the IPhone 8 and facing multiple issues. My cell phone automatically switches off and then switches on. Sometimes becomes dead also and does not start unless reboot. One of my friends said that there is some hardware problem."