Spent good time and money building a coop with automatic door for my chickens and they refuse to go inside. Its plenty big. 5x8 for 4 chickens with a 12x12 yard. They will go under it to sleep but never in it. Granted they have only been in there for just under 2 weeks, but how can I get them to take to going inside. The door is about 13x13 and about 15 inches of the ground.