Thanks for your reply!
What is your Outlook client version? Please make sure to update to the latest version.
Can your account be logged in to other M365 products, e.g. Teams, Word, OneNote, etc.
Try creating a new profile to add the account in question. Go to the Control Panel>Mail (Microsoft Outlook)>Show profiles>Add.
Once the profile is added, select the newly added profile > Properties >Email accounts>New>Fill in the account password (please make sure it is correct)>Next>Finish>Restart the Outlook client.
Hope this helps!
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