I'm going to untip my hotel cleaning person
Why would you "untip" someone?
He forgot to wash my shirts and I had to do it myself.
Everyone makes a mistake sometimes. It is rude to not give a tip to someone for the work they did do.
He doesn't even deserve a stupid tip.
Well if you've already given the tip it would be horribly rude to take it back now. Just don't tip him again if you don't like the job he's doing.