i was try this Reset NVRAM on my macbook pro but still show lock folder anyone know how to fix?

hi guys

Resetting NVRAM

1. Shut down your Mac.
2. Locate the following keys on the keyboard: Command (⌘), Option, P, and R.
3. Turn on your Mac.
4. Press and hold the Command-Option-P-R keys immediately after you hear the startup sound.
5. Hold these keys until the computer restarts and you hear the startup sound for a second time.
6. Release the keys.

but dont have startup sound for a second time. just startup one time show lock profile only , i try to key in my user password was not use , did anyone know how to fix ?