We've had chickens for 30+ years, but run into a new problem. We have 19 Black Australorp that are 18 weeks old. About 3 weeks ago we introduced to our main coop with 3 hens and 1 rooster. They get along fine and finally got the new ones to go in the chicken house at night. After about 10 days of closing the door at night they got to where they will go in the chicken house on their own and stay without shutting the door. Our problem is they gather on the floor of the chicken house in a corner. I've tried putting them on the roost, but they head right back to the floor. They want nothing to do with the walkway to the roost or the roost. Since the nesting boxes are by the roosts I need to get them used to going to the higher level. Never had this happen before. Any suggestions?