Arquivet Fresh Free-Range Duck - dog dry food

After my Akita-Husky mix practically inhaled the first 2.5kg bag within just over a week, he now won’t touch the next 2.5kg bag or its contents, which seem to have changed both on the outside and inside. How can this happen with two orders just a few days apart? I’m disappointed and will now donate the food, and in future I’ll buy from a specialist shop again—at least there I can see straight away if a bag suddenly looks different.