"HELP WITH LOCK IN RECOVERY MODE: Hi everyone. When I start recovery mode on my MacBook Air 2015 it shows me a lock and when I enter the password it automatically clears. Already once I was able to enter recovery mode to repair using disk utility but I can't do it anymore."
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Thank you for the photo.
Lock Before Recovery Mode:
You have a firmware password. That is what you need to enter. When you formatted hard drive, you would have encrypted it, which you would have been required to create a password. So, if you don't know the password, then you just can't get into it. So, enter a few password for thought.
Go Here: If your Mac doesn't Start Up All the Way - Apple Support
Scroll to: Lock icon
As it reads: "If your Mac is using a firmware password, the lock icon appears when you try to start up from another disk or volume, such as an external drive or macOS Recovery. Enter the firmware password to continue."