got the same problem, tried:
- reboot iPhone
- reinstall outlook
- reset account
- remove the account and add it back in
- goto web interface and have everything in the mobile device section removed
- having everything deleted and log back in
non of these would work.
the customer service chat was extremely not helpful
the guy: ok what version of outlook you are using?
me: what? it's ios
the guy: so we have two outlooks, outlook and outlook new
me: what? what is that
the guy: can you check what office plan you are on
me: what? it's ios
the guy: yes I understand but outlook is part of office and it requires subscription
me: what are you even talking about, I am on free account and trying to read my email on ios
the guy: yes but you only mentioned it's free account without telling me the subscription
me: (screenshot)
the guy: ok it looks like you are using outlook legacy, you need to go to the corresponding team for that
me: so hold on, what is that new app? I didn't see that in the app store.
the guy: the new outlook is a new windows application and not working on your device
THEN WHY THE HELL asking me like a paranoid in the first place? you know it's a new windows app, you know I am on ios, you know that Outlook email doesn't need any sort of subscription, why the hell you ask? if you are Windows team or outlook.com team, and you know I am on the ios, why the hell do you have this useless conversation continue?
WHY?