cygwin ssh connection OK via localhost, but not via 127.0.0.1

Question

I've installed Cygwin and OpenSSH server on it.

Cygwin version is 2.2.1(0.289/5/3) and OpenSSH version is 7.0p1-1

After some configuration, I can connect on my SSH server with:

$ ssh username@localhost
username@localhost's password:
Last login: Sat Aug 22 13:37:06 2015 from ::1

But, I couldn't connect on my SSH server with:

$ ssh username@127.0.0.1
username@127.0.0.1's password:
Permission denied, please try again.
username@127.0.0.1's password:
Permission denied, please try again.
username@127.0.0.1's password:
Received disconnect from 127.0.0.1: 2: Too many attempts.
Disconnected from 127.0.0.1

I am very confused since I have no idea about what's the difference between localhost and 127.0.0.1

For more detail, I've described ssh_config and sshd_config in here