@Tarun Mehta Based on the error message ,looks like Active Directory setup issues (Sites & services) also there could be possibility of password sync issue. We need to look closer on this issue and requires deeper troubleshooting, I would recommend you to contact support, so If you have a support plan, I request you file a support ticket, else please do let us know, we will try and help you out with different options.
Please let us know if you have any further queries. I’m happy to assist you further.
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