I have a quest that says "Breed a Mushroom double Premium Irish Sport Horse." It must be a bug since no matter what I try or type in the hors search, nothing comes up, I even click the gene test button and nothing, ive asked other players and they can pull it up but I can't?

What exactly are you typing into the horse search?

If you are trying to look for mushroom ISH, bear in mind that mushroom is a recent addition to the game and is only found in PONs. It needs to be bred from PON to SH to ISH :)