Same with my pup. She is 5 months old and I noticed big scabs on her head whrnigot her and chunks of hair coming out with them. It seemed to clear up. Now there are no scans but her hair is falling out in God awful amounts. She has flakes and bald armpitsI'd have a vet check. He's at a "good age" for demodex to rear it's ugly head. And it could be nothing or something in between.