on Debian, the default for "sshd" is "enabled = true" defined in /etc/fail2ban/jail.d/defaults-debian.conf.
I have overridden this in /etc/fail2ban/jail.local (the .local files are read after related .conf files) to "enabled = false"
when browsing "filter action jails", sshd is reported as enabled (incorrect), although entering sshd show
enabled "no" (correct)
Can you attach that /etc/fail2ban/jail.d/defaults-debian.conf config file to this bug report, or paste it in?