Microsoft 365 Login Issue

Question

Microsoft 365 Login Issue

Michael dela Cruz 0

Dear Microsoft Support Team,

I am experiencing an issue while trying to log in Microsoft account. Although I can successfully sign in to my personal Microsoft account, but when attempting to access our Company Microsoft account, I am prompted to verify my identity. However, when I select phone verification, I receive the following error message:

“Sorry, we’re having trouble verifying your account. Please try again.”

When i try to login again the account is already signed in, but when i try to verify it, the error still occurs.

This issue started recently, when i clean up my temp and history files because my computer is getting slower, then the problem occurs when im trying to log in again and I need access to manage our services.

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I have already tried alternative login methods and password reset options but have been unable to complete the identity verification process.

I was thinking that because I don't often use the Phone Number for a long time to verify the account, since it's save on my computer.

I would like to clarify that the phone number has not been involved in any malicious behavior. I only use it for login verification as a precautionary measure.

I would appreciate your kind assistance in resolving this issue as soon as possible. Please let me know if any additional information is required.

Thank you for your support.

Best regards,

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1 answer

Your answer

Answer 1

Jade Ng 14,780 Microsoft External Staff Moderator

Dear @Michael dela Cruz,

Regarding the issue where you are receiving error code 399287 and are unable to receive or use the SMS verification code to sign in, I’d like to ask a question to better understand your situation and assist you more effectively.

Could you please clarify whether you are an end user or an admin?     

If you are an end user, I would recommend you contact your account's Admin to reset your MFA settings through the Microsoft Entra Admin Center. Ask your administrator to follow these steps:       

Sign in to the entra.microsoft.com as at least one Authentication Administrator.
Select User > All user. Select the user (your account) to act on and select Authentication methods then select Require re-register of multi-factor authentication.

Require re-register MFA: This disables all previous authentication methods. You'll then be prompted to configure a new MFA authentication method the next time you try to sign in, so you can set up from the start and add a new authenticator app.

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For step-by-step details, see the official Microsoft documentation: Manage authentication methods for Microsoft Entra multi-factor authentication - Microsoft Entra ID | Microsoft Learn

If you’re unsure who the Global Admin is within your school account's organization, you can find guidance on locating them here: How do I find my Microsoft 365 admin? - Microsoft Support

Note: Once re-registration is triggered, all your existing MFA methods such as phone numbers, Authenticator app, or other verification options will be removed. You will need to set up new MFA methods during your next login. Please ensure you have access to a valid phone number or the Microsoft Authenticator app before attempting to sign in again.

Please feel free to contact me if you are an admin. I appreciate your patience, and I am here to help. Looking forward to your response!

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Michael dela Cruz 0 Reputation points

2026-07-24T05:23:29.68+00:00

Thanks Jade, we'll try this steps Thank you again
Jade Ng 14,780 Reputation points Microsoft External Staff Moderator

2026-07-24T05:29:24.0266667+00:00

Dear @Michael dela Cruz,

Thank you for your response!

Please let me know whether the issue has been resolved after trying the steps above.

Thank you for your cooperation and I appreciate your patience and understanding.

I look forward to hearing from you. Have a wonderful day ahead!
Michael dela Cruz 0 Reputation points

2026-07-24T06:32:52.2866667+00:00

Hi Jade,

We've tried to sign in at entra.microsoft.com but still it redirects us to here
Jade Ng 14,780 Reputation points Microsoft External Staff Moderator

2026-07-24T06:35:37.84+00:00

Dear @Michael dela Cruz,

Because this issue is related to Microsoft Authenticator and MFA, it will require assistance from your organization's IT administrator.

I recommend sharing the troubleshooting and MFA reset/revocation steps I provided earlier with your IT department and asking them to follow those steps.
Jade Ng 14,780 Reputation points Microsoft External Staff Moderator

2026-07-25T04:05:45.3+00:00

Dear @Michael dela Cruz,

I hope everything is going well on your end.

I’m following up on the support thread we've been working through together. I wanted to check in and see if the information I shared in my previous answer helped clarify the issue you were experiencing.
Michael dela Cruz 0 Reputation points

2026-07-27T01:52:07.2566667+00:00

Hi Jade,

Sorry for late reply, even the admin can't login to our microsoft account, because of the phone number maybe block, but the phone number is still active and usable
Jade Ng 14,780 Reputation points Microsoft External Staff Moderator

2026-07-27T03:28:45.0433333+00:00
Dear @Michael dela Cruz,

Thank you for your update!

Could you please clarify whether your IT administrator encounters the same error when signing in to the Microsoft 365 Admin Center? The steps I shared earlier are intended for your IT administrator to reset your MFA configuration by disabling the previously registered authentication methods and helping you set up a new Microsoft Authenticator app from scratch.

However, if all of your IT administrators are also locked out of the Microsoft 365 Admin Center and unable to sign in due to the same authentication issue, the best course of action is to contact Data Protection directly.

Method 1: Contact Microsoft Data Protection Support by Phone

For a full list of regional numbers, you can also visit this official page: Customer service phone numbers - Microsoft Support. The support team will assist you as soon as possible. If you can reach Microsoft by phone, use the official Global Customer Service phone numbers list. Choose your region > your country > if your country lines fail or lack English support, select a nearby country or the United States number, Microsoft explicitly allows this.

Method 2: Create a Temporary Account (Trial Tenant) to Submit a Support Ticket

If you have difficulty reaching an agent by phone, there is a reliable workaround. This involves creating a new, temporary Microsoft 365 account to contact the support team online.

1.Visit the Microsoft 365 Enterprise Plans page: Go to Compare Office 365 Enterprise Pricing and Plans | Microsoft 365.

2.Choose a plan and start a free trial: Select any of the available plans and click "Try for free" to begin the trial setup process.

3.Follow the guided setup: Complete the steps to create a new Microsoft account and a new tenant. This will be a separate and independent Microsoft 365 environment.

4.Access the Microsoft 365 Admin Center: Once the new tenant is created, navigate to https://admin.microsoft.com/AdminPortal/Home#/homepage

5.Go to Support: In the left-hand navigation menu, click on "Support" and then "Help & support."

6.Raise a support ticket: Describe your issue in detail. Crucially, you must clearly state that you are locked out of a different, pre-existing Microsoft 365 tenant where you are the administrator. Provide the following information about your locked account:

Your administrator account email address for the tenant.

The domain name of your tenant

Any error messages you are receiving.

Details about the issues you are experiencing

Confirmation that you are the administrator of the tenant.

7.Submit your ticket:

Follow the prompts to submit your support request. You will likely receive a ticket number for tracking.

Important notes:

This new trial tenant will not give you access to any of the data or settings in your original locked tenant. It is solely a temporary means to contact Microsoft support.

Be prepared for Microsoft support to ask for verification of your identity and administrative rights for the locked tenant.

The resolution time might be longer as you are contacting support from a different tenant.

Remember to cancel the trial subscription for the new tenant once your issue with the original account is resolved to avoid any unintended charges. You can typically do this within the Microsoft 365 Admin Center under "Billing" > "Your products."

I hope these steps will help resolve your issue. If you need further assistance, I am always here to help.

Thank you for your patience and understanding. I appreciate your continued trust. Hope you having a nice day and really much warm regards to you as well!