ssh says: You don't exist, go away!

The error message is probably coming from ssh on your own machine. Source

This happens if ssh can't find your username in the passwd database.

You can try running getent passwd $USERNAME multiple times and seeing if that fails.

Depending on how passwd lookup is configured, try one of these:

• Ensure your username appears in /etc/passwd
• Ensure that sssd or nscd is running properly, if appropriate
• Ensure that your connection to the account server, e.g. NIS, LDAP, etc. is working
• Check the system log files on your computer (/var/log/messages, /var/log/syslog, etc.)

If you post the output of grep '^passwd' /etc/nsswitch.conf, along with any interesting parts of ssh -vv output and system logs, people can probably help more.

If you change an account's UID, any existing shell will have this sort of identity crisis. Check by comparing UID from output of "id" and do a grep $(whoami) /etc/passwd. if changing UID, be sure to check for any crontab entries for the user!