Translated articles and indexing

I have about 4000 articles on my blog;
2000 Italian and 2000 translated into Spanish

in each Italian article, I have added the corresponding hreflang to the article translated into Spanish in “code injection”, for example:

<link rel='alternate' hreflang='es'

the result is the following in google search console:
2400 pages indexed correctly (those in Italian)

In excluded pages:

"Alternative page with appropriate canonical tag (2305)": these are only AMP articles but with a mixture of Italian and Spanish pages

"Pages with redirection (2160)": there is a mixture of Italian and Spanish non-AMP pages.

I don’t understand why all Italian and Spanish pages shouldn’t be indexed.
Is hreflang revealed by google as canonical?

Furthermore, Italian pages should not be detected as “redirected and non-indexed pages”

Did I do something wrong?