Hello everyone. My bird has been really itchy around his beak as of recent and as result.. started losing feathers from the scratching. He has been taken to a vet and they have not found any mites.. they did give us a powder to give to him anyways(which we have been using). His itching is definitely not as bad as before and some feathers are started to grow back. I am however noticing the yellow like substance around the feathers that are growing. Is this normal?(Best pictures I could get with him moving so much haha.. you can see it when zooming in to the cheeks).