GarzaMomma Said:
"Why is my child’s screen time randomly turning off on its own? They do not have the passcode: [...]My daughter comes to me when she notices it, and I have to go back in on my phone and fix it. Why is this happening??"
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Troubleshooting Screen Time with a Black Screen::
The issue is either (A)Screen Time is blocking it out bases on your settings, or (B)the screen is black and you need to fix that.
A. Troubleshooting Screen Time:
Make sure Screen Time is Set Up Correctly. Go Here: Use Screen Time on your iPhone, iPad, or iPod touch - Apple Support
B. Troubleshooting a Black iPhone Screen:
Try Swiping-Down from the top-right corner of your screen. See if that rids of this window. If not, I'd say the iPhone is stuck in a boot loop(because it was updating), or is simply frozen. So, if swiping down does not work, refer to the following... Use my User Tip: How to Fix an iPhone in a Boot Loop - User Tip
No success?...
Try the Tips at these Apple Support Links: