Hi @northport,
Looking at the error, there seems to be some Access Control Policy applied to Microsoft Office 365 Relying party that requires MFA to be performed and since MFA is disabled, authentication is failing at second factor.
On ADFS, global authentication method can also be configured to require MFA but as one user is getting this error I am suspecting it is not configured at global level but by specific Access Control Policy on the O365 RP.
Please check the access control policies on the O365 Relying party on ADFS Server and remove any policy that requires MFA to be performed. For more details on access control policies in ADFS, please refer to https://learn.microsoft.com/en-us/windows-server/identity/ad-fs/operations/access-control-policies-in-ad-fs.
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