Your Organization has blocked your account

This usually means the account is being treated as a work or school account, or it is still associated with an organization tenant.

Try these steps on the iPhone:

1. In Outlook for iOS, remove the affected account.
2. If Microsoft Authenticator is installed, open it and remove any old work or school account entry tied to that Outlook sign-in.
   • Warning: removing an Authenticator account stops that phone from approving sign-in requests for that account.
3. If Intune Company Portal is installed, open it, go to Devices, select the iPhone, and choose Remove device.
   • Warning: unenrolling can remove access to organizational email, apps, Wi-Fi, VPN, and other protected resources.
4. On the iPhone, go to Settings > General > VPN & Device Management and check whether an old management profile is present. Remove it if allowed.
5. Restart the iPhone.
6. Open Outlook and add the account again. If Outlook suggests a cached organizational account, choose Use another account and manually enter the Microsoft 365 account.

If the account still shows as blocked by an organization, the most likely cause is that the address is still associated with an organization tenant. In that case, the account must be removed from that former organization by that organization’s Global Administrator.

If the issue is instead a blocked Outlook.com/Microsoft account, use the Sign-in Helper. If unblocking with a security code or password change does not work, use When you can't sign in to your Microsoft account.

If Outlook for iOS is connected to a Microsoft Exchange account and that account is disabled, the documented resolution is to contact the Microsoft Exchange administrator.

References:

• Cant remove an organisation - Microsoft Q&A
• Unable to remove Outlook and Teams from IPhone - Microsoft Q&A
• Unblock my Outlook.com account
• Why is my Microsoft Exchange account disabled?