How to query an object in field array in Firestore

Hi, I have the following structure in a firestore document:


How do I search the email field?

If it’s just a string type the following image 2 can do with:

ref.where('confirmados', 'array-contains',

But, how to do when the array is an object according to image 1?

I was able to solve with the structure of my firestore.
I’m using maps with keys on both sides of the collections for easy searching.