1. Kindly change the perches with natural wood. Neem is best. They will chew on them. 2. Remove any artificial item such as swings made of plastics. 3. Provide them with enough calcium. Give them cuttlefish bones for minerals or mineral block. They might not bite them every time but they will chew on it one day or the other. Make sure to keep those calcium sources on same lever as perch
