168 hours of screen time

I am very confused by the results I am seeing from the Screen Time feature on my iPhone 7 plus. For the past two weeks it reads as if I never set my phone down saying I used my phone for 168 hours last week and my daily use is 24 hours a day. Unless I am just daft and can't read the data properly, my phone must think I do not sleep or work! I have searched for answers, restarted and reset my phone, and still for all last week it recorded my uses as 168 hours of screen time. Now I'm just irritated! Do I just have a glitchy phone, or am I reading this all wrong?? Thanks for the help!