Hi Phu,
Thanks for reaching out.
The only way to get your account back is by using the Account Recovery Form: https://account.live.com/acsr. You can submit the form twice every 24 hours, so if you remember more details, give it another shot. For security reasons, Microsoft's recovery is automated, so support can't manually check your identity or bypass the system.
If your request to get your Microsoft account back didn't work, click this link for details: https://support.microsoft.com/office/dc56c3e3-dff0-4ed5-8edb-60290eea6b53
Could you confirm if two-step verification was ever turned on for this account?
Let me know how it goes. If you found this helpful, marking it as helpful might make it easier for others to find the solution. Thanks!
Regards,Carlo