Does anyone know the reason for this error code?

thanks Anonymous . I understand that the device wasn't found in tenant. But can you please explain what might cause the device to be not found in tenants? Because as far as I know nothing has changed on the device. 

Also, this error was generated when Power BI tried to send a report subscription to the user's outlook email. So I fail to understand why a physical device authentication error was thrown? Because regardless of whether the user was properly authenticated on any of his devices or not, as long as the email address was valid, the subscription email should have been delivered anyway.

From my research it sounds like an expired/invalid authentication token issue. But then I don't understand why the token would expire or become invalid in the first place? Every other person in the organization received the subscription email just fine including me. And these are all corporate devices (phone, laptop), so they all have the same security settings.