My other account can't log in and it reports that the user doesn't exist

As your issue description is primarily written in English, I will provide my response in English for your convenience. Please feel free to let me know if you would prefer the information in another language.

Hi @NGUYỄN TÂM MINH NGUYỆT - D21,

Welcome to the Microsoft Q&A forum, and thank you for reaching out regarding the issue you are experiencing with signing in.

Based on the information you shared, it seems possible that the organization associated with the account may not have been active for some time. In many cases, this may depend on whether the organization’s environment is still within Microsoft’s retention period. If the tenant has not been active for a long time, there is a possibility that it was fully deprovisioned, and recovery options could be very limited.

At this stage, the best next step is to contact the organization’s IT administrator to confirm whether the environment is still maintained and whether any form of account or data recovery is possible.

• However, if you are an administrator for the organization, you may be able to contact Microsoft Support to check whether the environment can still be verified or restored by reaching out to Global Customer Service phone to raise a support ticket here: Customer service phone numbers - Microsoft Support.

During the call, request to speak to an agent, and share with them every detail related to your query. This should allow you to contact the appropriate team so you can solve this incident as soon as possible.

Please note that forum moderators do not have access to user account settings and cannot assist with logging in, resetting passwords, or changing access rights. While we do not have access to internal systems or administrative tools required to resolve account-specific or backend-related issues, we’ll continue doing our best to support you within the scope of our responsibilities.

• If you cannot reach a live agent, there is still a workaround, you might consider registering for a new tenant by signing up for a trial subscription via this link Microsoft 365 Business Plans and Pricing | Microsoft 365.

(Please select "Try for free" under a subscription)

This would allow you to create a new tenant following the prompts provided. Once set up, you can access the admin console of the new tenant and submit a support ticket requesting to speak with the Data Protection team on behalf of your previous tenant.

To create a support ticket: In the Microsoft 365 admin center > Support > Help & Support.

In your ticket description, you'll need to clearly explain that you're trying to regain access to your previous Microsoft 365 tenant and need help from the Data Protection team.

I hope this information is helpful. Thank you for taking the time to raise your question. If you have additional questions or need further assistance, feel free to let me know.

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