Switching food and puppy is a bit reluctant to eat

My puppy used to eat like she was starving, but now that I’ve slowly switched her food (I think she might of been allergic to her first food – chicken) she won’t immediately start eating, and sometimes needs encouragement to start eating, and to finish. Can this be normal when switching foods, or is she just not a fan? She eats it just fine as treats, but is a little weird at meal times now.

Thanks!