@Richa Kumari, Thanks for posting in Q&A. From your description, I know the Windows 365 PC is provisioned but unable to login. From the error, it seems the Azure AD join is failed. But no detailed error there. You can export logs to see if more finding. To protect your sensitive information, you can also consider opening case to troubleshoot the issue. Here is a link with the steps to open case:
https://learn.microsoft.com/en-us/mem/get-support
Hope the above information can help.
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