Why does Guided Access stop working on iPhone 16 Pro Max, requiring a phone reset?

Re:" I use guided access when my kids use youtubekids (iPhone 16 pro max) but every few days I have to reset my phone to get guided access to work again. I do nothing different, it just stops working until I reset my phone. Anything I can do to stop this from happening? "

Accessibility apps may work a little differently from the regular apps.

Wondering if you have set-up Guided Access as Apple support suggests.

ie: so you can start it when the kids are about to begin using it,

and

end a Guided Access session when you want to begin using the phone for everyday use again.

Eg: Use Guided Access with iPhone, iPad, and iPod touch - Apple Support

says:

Set up Guided Access

1. Go to Settings > Accessibility, then turn on Guided Access.
2. Tap Passcode Settings, then tap Set Guided Access Passcode.
3. Enter a passcode, then re-enter it.

From here, you can also turn on Face ID or Touch ID as a way to end a Guided Access session.

Start a Guided Access session

1. Open the app that you want. 
2. On an iPhone X or later, triple-click the side button. On an iPhone 8 or earlier, triple-click the Home button.
3. If you want parts of your screen to stop responding to touch, use one finger to circle those areas. You can move or resize the circle, or tap the X to remove it.
4. Tap Guided Access, then tap Start.

Or to start a Guided Access session with Siri*, open the app that you want, then tell Siri "Turn on Guided Access". 

*Siri features may vary by country or region."

"End a Guided Access session

Triple-click the Side or Home button, enter your Guided Access passcode, then tap End.

Or if you turned on Touch ID or Face ID for Guided Access, double-click the Side or Home button."