The Dunlop 3D tires are directional tires. So they can be installed either way.
However, they must be put onto the proper side of the car.
Each tire will have an arrow on it showing the direction of rotation (which should be pointing towards the front of the car with the arrow at the 12 o'clock position).
Perhaps someone did a bad rotation on them?
Take it back to where you had it installed along with the receipt and have them do it over again. should be free.