APM Kerberos Authentication - Logon agent instance is not available to be scheduled

Update: after adding a Debug logging policy on the relevant APM policy I found that the password for the Active Directory user account that I have tried to authenticate has been expired. It's to bad that the APM doesn't log that in the default logging policy.

AD agent: Auth (logon attempt:0): Domain password has been expired and must be changed for 'User@Domain.com'

After resetting the user password the authentication succeeded.

Thanks Kevin.