Dear Dundi Akhil,
Good day! Thank you for posting to Microsoft Community. We are happy to help you.
I carefully went through your question, and it seems you are trying to restore a deleted user account in Microsoft 365, but you are getting an error message. I am sorry for the inconvenience this issue has caused!
When users are deleted from Azure Active Directory (Azure AD), they are moved to a "deleted" state and no longer appear in the user list. However, they are not completely removed, and they can be recovered within 30 days. From your description, it is not yet up to 30 days, therefore, you should be able to recover this user.
Please let us work together and resolve this issue. May I know what steps you are using to recover a deleted user? did you check this article? If not, please check this article and follow the suggestions to see if you can restore this user: For reference, see How to restore deleted user accounts in Microsoft 365, Azure, and Intune - Office 365 | Microsoft Learn.
If you still can't restore the user, please share the screenshot of that error message and we do further investigation, and tell us the steps of reproducing that error.
Thanks for your kind understanding and cooperation. Good luck and stay safe!
Sincerely,
Edwine | Microsoft Community Moderator