How old is Bella? From what I have read and what several vets have told me, the more you try different foods the higher the chances are of them acting that way. What food did Bella start with at the very first?
Remember that a dog will never go hungry if there is food in a dish. Bella is working hard at telling you what to do. I have had stubborn ones go almost all day with out food. With small dogs you do have to worry about blood sugars, but Bella is eating even if it is only a bit.
If you can, try going back to the original food and only put a little bit in the bowl. Take Bella out for a really long walk or play for an hour or so. Then give Bella the food. After 10 minutes, take it away and wait. In a couple of hours, another walk and give back the food. Alway keep water available at all times.
Be patient and good luck.
