I tried changing the password and username in my laptop and logged out. Now when I try to login it asks not only for the password but also for the username. I used both new and previous usernames and passwords but still couldn't do anything.
MacBook Air 13", macOS 10.12
Change the name of your macOS user account and home folder - Apple Support
The name of your macOS user account and the name of your home folder must both be the same.
Changing these names does not change or reset the password of your user account.
Because doing this incorrectly could damage your account and prevent you from logging in, you should back up your important data before proceeding.
Can't login to my MacBook
