Put your phone in fastboot mode, then connect it to your computer. Then check in cmd (command prompt) if your device is detected by the computer. Use platform-tools of Android, or download MiFlash tool (if you haven't already) and check there if...
how about hindi sya naka debugging mode boss? kase na Mi Account lock sya hindi na na-on ung debug mode any other options para maconnect sa pc ung cp po