How to fix my Apple ID that is not active?
Hello! So i gave my iPhone 12 Pro Max to my Grandma. I reset all of the settings. After connecting it to the WiFi, An Apple ID Prompt that she needs to be log-in. So in her iPhone 12 Pro Max, I created her an Apple ID and it works. But when she needs to install an application on App Store, the application could not install because the App Store still needs Apple ID to log-in. Then after typing her Apple ID and Password it didn't log-in. The color red text shows "Apple ID is not Active".
Please help me to fix this issue. Thank you!
[Re-Titled by Moderator]
iPhone 12 Pro Max