Context:
And its not the first time this has happened. A few weeks ago I had 2h of screentime before i woke up, sometimes it said youtube, sometimes other apps, but around the same time.
I "fixed" this by turning my phone upsidown, so the sensors are on the desk, and i closed all of running apps in the background before going to sleep.
But this is not a solution, its a temporary fix.
Since i got the iphone, It registered screentime correctly only a few times. I spend at most 2h a day on the phone, but my average is almost 5h because of this "bug"