You may have a bent or warped disc. This happens much more easily than one would expect. You will have to remove the disc from the hub and lay it on a perfectly flat surface to see. If it is you can try remounting it and make sure the torx screws are snug. Tighten them the way you would when changing a car tire in an X pattern. Then try gently but firmly bending the disc in the opposite direction in the spot where it is rubbing. Some people have used thin washers behind the disc in the closest mounting hole but I would recommend a new disc.