Wyandottes are supposed to have rose combs.
In future, if you want to buy a Wyandotte, check for the flat little rose comb on the chick-- if it has a skinny single comb, look for a different chick. Single comb is the kind that looks like a comb you might use on your hair: skinny, stands up, has points on the top.
It also helps if you look at pictures online to learn what the down color & pattern look like, if you want to buy a particular breed & color of chick. That can help avoid some of the other "wrong" ones.