IceMan2011F Said:
"In app purchases under a family plan.: How do I add a payment method when my phone is under a child account and it grays out the 'add a payment method' button? How do I verify a credit card when it doesn’t let me click on its status to do anything?"
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Troubleshooting Family Plan Payments:
A. Adding a Method of Payment to a Family Plan:
Talk to the person who operate this device's Family Plan. They need to add it. Or is this you?
B. Have At least One Method of Payment:
Note: You need at least one method of payment assisted to your Apple Account. This is because even free apps have the option to purchase items form within them.