Using Outlook for iOS for personal email and calendar management
Hello, thank you for reaching out to Microsoft Q&A.
It’s asking for your iCloud (Apple ID) password.
If you’ve forgotten it, please try resetting your Apple ID/iCloud password, the same one you use for the App Store.
Typically, the iPhone will use Face ID (or Touch ID) for app installations. If you haven’t set this up yet, or if it prompts you to enter a password when you tap Install in the App Store, you’ll need to enter your Apple ID/iCloud password instead.
See,
If you forgot your Apple Account password
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