Definitely old enough to be flying then. Do they come in to the loft when you call them? You have to chase them somehow... throwing a ball, spraying with water... whatever gets them in the air and moving. You can't have them sitting places where you don't want them to, or not flying while they are out without punishing them for it. It's a bad habit that has to be broken. And then if you call them in and they trap and you then feed them it even further reinforces that bad behavior because they are receiving a reward when they did absolutely nothing. With young birds it can be a pain at times depending on the birds. Sometimes it's just one bird that's holding back the whole flock, and if you can find it and pull it from the group the others will take off.The yb are just over 2 months. They had never flown as I hatched them at the new property. I haven’t been able to flag as they will sit on the top of our house and or garage once I get them off the loft roof. I had heard maybe a tennis ball?