Not surprised at 11 weeks he is still a baby. Try some veg mash...this can be warm, but must not be too hot as can scald the crop. Sweet potato, butternut squash, broccoli are good ingredients especially for the Amazons who need a diet rich in beta-carotene, the precursor to Vitamin A. You could try softening pellets in a little orange juice. It’s an ideal time to get him used to as wide a variety of veg and fruit as possible.