Why does my iPhone show incorrect Screen Time?

Yesterday I was on my phone for about 4 minutes, or so says the broken times all added up together- I really spent 4 minutes. But my Iphone says I spent over 4 hours in total, with over 4 hours of grey( the grey that is used to show the time you spend in between each use of different applications). I want to know why. I don't have any other device connected to my apple account that anyone uses. Does anyone have a solution to my problem? Thank you for your attention.

[Re-Titled by Moderator]