@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that a host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
SHA256:XXXXXXXXXXXXXXXXXXX
Please contact your system administrator.
Add correct host key in /Users/{USER}/.ssh/known_hosts to get rid of this message.
Offending RSA key in /Users/{USER}/.ssh/known_hosts:1
RSA host key for github.com has changed and you have requested strict checking.
Host key verification failed.
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

github.com ssh-rsa XXXXXXX==
...略...

# Host {HOST} found: line 1
/Users/{USER}/.ssh/known_hosts updated.
Original contents retained as /Users/{USER}/.ssh/known_hosts.old

The authenticity of host 'github.com (XX.XX.XX.XX)' can't be established.
ECDSA key fingerprint is SHA256:XXX/YYY/ZZZ
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'github.com' (ECDSA) to the list of known hosts.
Warning: the ECDSA host key for 'github.com' differs from the key for the IP address 'XX.XX.XX.XX'