Guideline 5.1.2 - Legal - Privacy - Data Use and Sharing
We noticed you do not use App Tracking Transparency to request the user's permission before tracking their activity across apps and websites. The app privacy information you provided in App Store Connect indicates you collect data in order to track the user, including Phone Number.
Starting with iOS 14.5, apps on the App Store need to receive the user’s permission through the AppTrackingTransparency framework before collecting data used to track them. This requirement protects the privacy of App Store users.
Here are two ways to resolve this issue: