Something is cancelling my authentication to Azure AD via DUO MFA after entering account username of Azure AD global administrator. I should get a pop up window from DUO to enter username and password, but instead I get a window that appears to open and closes and a message “Authentication request was cancelled. Learn More” in the AAD Connect application. I believe it is a Windows Server 2019 or AADCONNECT issue but am investigating DUO MFA also.
Troubleshooting Azure AD connectivity via logging into login.microsoftonline.com, microsoft365 and portal.azure.com shows connectivity as does entering an invoke-webrequest -uri adminwebservice.microsoftonline.com/ProvisioningService.svc in powershell returns a 200 or OK status.
Nothing shows up in the event logs on the server. Windows Firewall being disabled shows no effect.