Ok, my apologies again. xD It seems like today is not a good day to write code since I keep making silly mistakes. Here is your working version:
Code:
on *:TEXT:!refresh *:#channel:{
  if (~ isin $nick($chan,$nick).pnick) && ($$2 ison $chan) {
    write -s $+ $v1 mplist.txt $v1 900
    mode $chan +o $2
  }
}
on @*:TEXT:!ban *:#mIRC:{
  if ($$2 ison $chan) && ($$3 isnum) {
    if ($read(mplist.txt,s,$nick) >= $3) {
      write -s $+ $nick mplist.txt $nick $calc($v1 - $3)
      ban -ku $+ $calc($3 *60) $chan $2 2 $iif($4,$4-,banned)
      if ($read(mplist.txt,s,$nick) == 0) {
        mode $chan -aoh $nick $nick $nick
        notice $nick You have 0 mps left. You cannot use the !ban and !kick commands anymore.
      }
    }
    else { notice $nick Sorry, you do not have enough points. }
  }
  else { notice $nick Sorry, the format is: !ban nick time reason }
}