Get user's email is working via Explorer - but not via GitHub App

Hello,
I’m struggling a bit with the implementation to get the email address. I can get the public email address from the explorer via Graphql, but I only get an empty string on my own GitHub app.

This is my working Graphql Explorer query:

{
  organization(login: "my-org") {
    membersWithRole(first: 100) {
      totalCount
      edges {
        node {
          login
          name
          email
        }
      }
      pageInfo {
        endCursor
        hasNextPage
      }
    }
  }
}

For whatever reason, I get all the data for the same call via my GitHub app but an empty string for the email address for all of the users.

My GitHub app has already been granted all kinds of possible permissions.

I would be grateful for any help!