Hello there I am having the same problem on my android using the outlook app. I keep getting asked to sign. I generated an app password and that did not solve it either. Following this thread
@mtls15789 Moved to a separate thread as your issue is different to that of the post you piggy backed on.
Following a password change, including generating an app password you need to delete the account from the Outlook app and then re add it with the full email address as the username and the generated app password.
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