Where's the best place to call methods that interact with my database?

I'm creating an app that interacts with a Firestore database. As of now I have a singleton class, DatabaseManager that has all the methods relating to the Firestore database (i.e. get/post methods).

I have a User model called User that has properties such as name, email, photoURL, and some app-specific properties. Any user can edit their profile to update information from a view controller called EditProfileViewController.

Now my question is: is it best to call the DatabaseManager.shared.updateInfo(forUser: user) (where user is a User instance) from EditProfileViewController, User, or some other place?

Sorry if this is an obvious question, but there's going to be a lot of points in the app where I'll need similar logic so I wanted to know what's the best design. Also I'm sure this question has more to with MVC than it does Firebase/Swift.