i took a request to write a script and i dont know why its giving me so much trouble but it is

the idea is that someone says brb and the script replies hurry back $nick
and the next thing they say triggers a welcome back $nick

the way i approached this; well one of them
was to have
on @*:text:*:#:{
  if ((% $+ $nick != on) && (*brb* iswm $$1-)) {
    set -s % $+ $nick on
    msg $chan Hurry back $nick
  elseif (% $+ $nick == on) {
    msg $chan Welcome back $nick
    unset -s % $+ $nick