If you are getting this error then try the following:
The built-in Administrator account cannot be disabled. I recommend you to check if there is an Administrator user account visible in safe mode and login to it to enable other admin user account.
Log out and go to the sign in screen.
Hold down the shift key on your keyboard while clicking the Power button on the screen.
Continue to hold down the shift key while clicking Restart.
Continue to hold down the shift key until the Advanced Recovery Options menu appears.
Click Advanced options
Click Startup Settings
Choose Enable Safe mode with networking
Wait while Windows 10 starts in safe mode.