No one has the right to do or say something that you aren't okay and/or comfortable with. Ask in a very nice, polite way for them to stop. If they don't ask them again. If you are a child then go to you're parents. If you are a teen or adult, walk away and ignore them.
Well if there calling on a cell 4 example. Just block the number. If it's the house line let the answering machine get it. If u ask them nicely and they don't stop then u might just have to pound on them a little.
well i would start making excuses that you have to go, and when you see them face to face, just get quiet and dont start conversation. the person might ask you whats wrong, so just say that you need alittle space.
but remember this person might also need a friend, so remember to be nice.