[v4] How to fetch data from a collection-type?

Hey, have you found a solution ? I think I’m encountering the same problem. My content has been published but when I try and type http://localhost:1337/api/collection_type_name?publicationState=preview it only shows me the first attribute which is correct, and then it prints the dates and that is all. I’ll add a pic.
Screenshot from 2023-07-19 10-52-33