Try this code,

Code:
ON *:TEXT:!whitebags:#: {
  if ((%wb) || ($($+(%,wb.,$nick),2))) { return }
  set -u30 %wb On
  msg $chan [ $+ $nick $+ ]: I have found %wbs whitebag(s).
}

ON *:TEXT:!swbs:#: {
  if ($nick == im_bad_atoot) {
    if (!$2) { msg $chan [ $+ $nick $+ ]: Error, Incorrect parameters, try again and enter an number! | return }
    if ($2 !isnum) { msg $chan [ $+ $nick $+ ]: Error, Incorrect parameters, try again and use only numbers and not any letters! | return }
    if ($2 == %wbs) { msg $chan [ $+ $nick $+ ]: Error, Already the same, try again and enter an other number! | return }
    set %wbs $2
    msg $chan [ $+ $nick $+ ]: You have set %wbs successfully.
  } 
}