Sheba, dicky tummy

I have expensive dogs when it comes to food I really do. I bought green pantry dog food for both my girls and turns out Sheba cannot eat it as she has an intolerance to as far as vet thinks as had her at vet twice this week alone. Nala staying on green pantry though as she seems fine with it.
This food is much more expensive than the green pantry for 12kg bag I hope this works but is only available by vets so we will have to wait and see