I ran into an issue today where my office router somehow got blocked by fail2ban. I searched high and low to find an answer to unblock it so I did not have to wait for the ban to expire.
Here is what I found:
when I executed
I saw that my IP was in the jail named postfix-spamers550
to remove it I executed the following command
fail2ban-client get postfix-spamers550 actionunban 111.222.333.444