Registration process has issue and resulted in duplicate of the same device on the registered device list
Solution:
Delete the duplicated devices on AAD
Send below steps to user:
[1] Go to Settings
[2] Select Apps
[3] Find and tap on Outlook and Teams
[4] Tap Storage
[5] Tap Clear Cache (bottom right-hand side of the screen)
[6] Open a web browser and go to outlook.office.com
[7] Enter your email and password
[8] Complete the 2FA process via the Authenticator app
You'll likely see an error message indicating that your device isn't trusted. When prompted, select Trust this device
