We have a similar problem. Our dog will eat the Royal Canin Yorkshire Terrier blend, but not every meal. This is the only food she will eat consistently. She will eat either in the morning or in the evening but not always. Sometimes she won't eat at all or she will eat both times. We never know. However, the cat will eat the Royal Canin if I leave it down, and it is too expensive to feed the cat since he will eat anything and everything (and weighs about 25 pounds!) So I put up the dog food if she doesn't eat, and when she begs for a treat, I get out her food or bring it out again in the evening for the next meal. She will eventually eat.