Hi spam4,
To troubleshoot, toggle Ask to Buy off and back on if this is happening with a child's account with the feature enabled. This may help to clear up the issue. To do so, follow these steps: Approve what kids buy with Ask to Buy - Apple Support
"On your iPhone, iPad, or iPod touch
- Open the Settings app.
- Tap your name.
- Tap Family Sharing.
- Tap your family member's name, then tap Ask to Buy. In iOS 15 or earlier, tap Ask to Buy then tap your family member's name.
- Turn on or off Require Purchase Approval."
Additionally, test after changing the Screen Time passcode for the affected account, and sure the passcode can't easily be guessed to help troubleshoot. To do so, tap Settings > Screen Time > (name) > Change Screen Time Passcode.
If you're using multiple devices, check and make sure "Share Across Devices" is enabled for each of your devices under Settings > Screen Time > Share Across Devices, as perhaps there's a syncing issue causing the behavior.
If the issue persists, reach out to Apple Support directly to help investigate and resolve the behavior. You can use the following link to reach out: Contact - Official Apple Support
Take care.