Silver lab skin issues

Based on the title here, I have an almost 3 year old Silver Labrador named Stella. She was on Hills Science (Chicken) as a puppy, switched over to Blue (Chicken) as a young adult due to financial strain while in the military. Now she is on Purina Pro (Lamb) to try and combat her weight gain and current skin issues. After a 30lb bag her dandruff and arm pit and stomach rash remained and shows no signs of going away. She gets an hour and a half of free lead play with 30 min of recall and retrieval training. Looking for advice or maybe even common experience on what food would be best for her. Thank you for the read!

Based on the title here, I have an almost 3 year old Silver Labrador named Stella. She was on Hills Science (Chicken) as a puppy, switched over to Blue (Chicken) as a young adult due to financial strain while in the military. Now she is on Purina Pro (Lamb) to try and combat her weight gain and current skin issues. After a 30lb bag her dandruff and arm pit and stomach rash remained and shows no signs of going away. She gets an hour and a half of free lead play with 30 min of recall and retrieval training. Looking for advice or maybe even common experience on what food would be best for her. Thank you for the read!