If family sharing is set up on your device, you may need to request authorization to make purchases.
If a system window opens by telling you to request purchase authorization, you will not be able to make a purchase by yourself. In this case, please send a purchase request to your family manager or discontinue the purchase. If the person accepts the purchase you want to make using the card associated with the family sharing, it will be automatically downloaded to your device.
If your device is designated Parent / Tutor and family members can not make purchases through Family Sharing, follow these steps:
1. Go to the camera settings.
2. Click iCloud -> Family. Select the family member who can not make a purchase.
3. Disable and re-enable the Request Purchase Authorization option, and then try to purchase from the device from which the request originated.