I had the exact same problem with my 8month old. Turned out it was a massive attention thing and her trying to see if she could get something else to eat if she refused. I left her in her pen with the food for 15minutes, when I returned she ate only a small amount. So I would take it off her. I did this everyday for a week. I feed her raw food and high quality dog biscuits.
But I just let her go hungry, and I tell you what, she eats every last bit now, because she knows if she doesn't eat it, she won't be offered anything else. Also we have 3 outdoor dogs, so they all have individual pens and are fed side by side, it really encouraged her too eat. Seeing the others eat convinced her she has too
Sent from my iPhone using Petguide.com Free App