When a server is rebuilt and you try ssh with the same name or IP, you may run into an error like this
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@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
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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
SHA256:a7RlObbYihpR9044e6LcxeIFwUUQnRT95Hho7+8aNxk.
Please contact your system administrator.
Add correct host key in /home/user/.ssh/known_hosts to get rid of this message.
Offending ECDSA key in /home/user/.ssh/known_hosts:96
Remove the offending key with this command. For example IP 192.168.1.84
ssh-keygen -f "/home/user/.ssh/known_hosts" -R "192.168.1.84"