@Dan Thanks for posting in our Q&A.
To clarify this issue, we appreciate your help to collect some information:
- On which app is this happening? Outlook app or iOS native mail App?
- Does this situation occur in unenrolled iOS devices? I find someone discussed this issue in Apple Community forum:
https://discussions.apple.com/thread/252015220
Note: Non-Microsoft link, just for the reference. - Based on my research, there are some methods to fix mail keeps asking for password on iOS. Please try and check if it works.
https://www.guidingtech.com/ways-to-fix-mail-keeps-asking-for-password-on-iphone/
Note: Non-Microsoft link, just for the reference.
Hope it will give you some ideas.
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