Why does my MacBook Air not accepting login password?

MacBook Air High Sierra

Laptop suddenly shutdown as battery was not charged and I removed charger.

Done earlier too with no issues.

But this time a strange issue appeared :

Entering correct login password but not accepting

Explored internet and found that many other users faced similar issue in various scenarios.

Found and tried some solutions but not working any

Tried methods like :

1.Multiple reboots

2.Virtual keyboard

3.Safe mode

4.Single user mode : removed .AppleSetupDone to trigger setup assistant to create other admin ac. But setup assistant not triggering

5.Recovery mode disk first aid

6.Changed password using Recovery mode

Anyone has any solution ?

Thanks in advance

[Re-Titled by Moderator]