If LINE cannot be used because age restrictions are applied (e.g. on your child's device), you can change the age restriction setting for apps. To do so, follow the steps below.
1. On your device, tap Settings.
2. Tap Screen Time > Turn On Screen Time.
3. Tap Continue > This is My iPhone or This is My Child's iPhone, then set the options on the screen.
4. Tap Content & Privacy Restrictions.
Note: If you're asked for a Screen Time Passcode, please enter the passcode set on the device.
5. Turn Content & Privacy Restrictions ON, then tap Content Restrictions > Apps.
6. Choose Allow All Apps, 12+, or another setting.
If you don't know the passcode you're asked to enter when changing the age restriction setting, please refer to Apple's Support page
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