cannot gain access to microsoft account.

The most likely causes in this scenario are:

1. The sign-in alias for the Microsoft account changed, so the email address no longer works as a sign-in name.
2. The account was compromised and the sign-in details were changed.
3. The address is being recognized as reserved or attached somewhere, even though it is not currently working as a usable sign-in alias.

Use this recovery path:

1. Go to the Microsoft account sign-in page and enter the exact email address.
   • If a password prompt appears, the email is a Microsoft account.
   • If the message says “We couldn't find an account with that username” or “That Microsoft account doesn't exist,” first verify the spelling and domain carefully.
2. Run the Sign-in Helper tool.
   • Microsoft states that most sign-in issues can be identified there.
   • If the account is detected, the tool provides the next steps.
3. If the account is not recognized and standard reset options fail, use the Microsoft account recovery form.
   • Use a working email address that can receive updates about the request.
   • Complete the form from a device and location previously used to sign in to that account if possible.
   • Microsoft reviews the answers and responds within 24 hours.
4. If two-step verification was turned on and none of the alternate verification methods are accessible, there is no supported recovery path through support agents.
   • Support agents cannot send password reset links or change account details.
5. Since there is a Minecraft purchase receipt, keep that proof of purchase available when contacting support through the public Contact Microsoft Support flow.
   • For technical support, enter the problem, select Get Help, and then Contact Support.
   • Support cannot directly reset the account, but this is the supported escalation path for technical review.

Important:

• Do not create a new Microsoft account with that email unless Microsoft confirms the original account is gone.
• If the account was compromised and the alias was changed, the original email can stop working for sign-in even though the account still exists.

References:

• I can't sign in to my Microsoft account
• How to check if your email address is a Microsoft account
• Help with the Microsoft account recovery form
• How to get a Microsoft account recovery code
• Account apperantly doesnt exist but when i try to make a new one with the same email it does all of a sudden - Microsoft Q&A
• Can't login - Microsoft Q&A
• Email is accidentally associated with two accounts - Microsoft Q&A