If you need help using your iPhone, iPad, or iPod touch, Exchange administrators might need your Exchange Device ID.
Find your Exchange Device ID in iOS 11 and later
Go to Settings > Passwords & Accounts.
Select Add Account.
Choose Microsoft Exchange from the list. Your Exchange Device ID is at the bottom of your screen.
If you restore your device to factory settings or move to a new device, you receive a new Exchange Device ID.
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