Event ID 4776 failure events on the domain controller, even username and password is correct

Hi Team,

I am observing failure event ID 4776 (The computer attempted to validate the credentials for an account with code 0xc000006a) is getting generated on my domain controller, even i am entering correct login details. can some one help me to understood this event.

As i know this event generates when NTLM authentication happens, but in my case i can see failure event with ID 4776.

If its bad password attempts then;

>> Account should get locked, but i cant see account lock or any event with ID 4740.

>> I cant see bad password count on lockout.exe.

Could some one please provide some information on event 4776, i searched google but not getting an proper information.