Why won't a yorkie eat?

Honestly, they could not be eating for a lot of reasons.

1.They don't like their food. In this case try new food.

2.They aren't comfortable in their surroundings. Try moving their food bowl to another place.

3. they might have a cold or flu. Take them to the vet's.

4.there could be a serious disease. Get them to the vet's as soon as possible.