$ ssh pi@xxx.xxx.xxx.xxx
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ 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 ECDSA key sent by the remote host is
xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx.
Please contact your system administrator.
Add correct host key in /home/xxx.xxx/.ssh/known_hosts to get rid of this message.
Offending ECDSA key in /home/xxx.xxx/.ssh/known_hosts:35
ECDSA host key for xxx.xxx.xxx.xxx has changed and you have requested strict checking.
Host key verification failed.
solution:
ssh-keygen -R xxx.xxx.xxx.xxx