Find the name of a CNContact's group (CNGroupName)

So I only recently uncovered the Contacts Framework through this video: https://youtu.be/sHKir2ZMk5Q. As such I'm not yet accustomed to the API. Basically my main problem is that I can't seem to find a way to access the name of the group a CNContact is in. The only support I can find is in Apple's own documentation, which isn't very helpful. if someone could point me in the right direction towards how to print the group name, I would be very grateful. My code is below, Cheers

//  ModelData.swift
//  B-Day

import Foundation
import Contacts
import SwiftUI

 struct Contact: Identifiable {
     let id = UUID()
     let category: String
     let firstName: String
     let lastName: String
     let birthday: DateComponents?
 }



 func fetchAllContacts() async -> [Contact] {
    
    var contacts = [Contact]()
    
    let store = CNContactStore()
    
    let keys = [CNContactGivenNameKey, CNContactFamilyNameKey, CNContactBirthdayKey, CNContactIdentifierKey, CNGroupNameKey] as [CNKeyDescriptor]
    
    let fetchRequest = CNContactFetchRequest (keysToFetch: keys)
    
    do {
        try store.enumerateContacts(with: fetchRequest, usingBlock: { contact, result in
                   
        //this should print the name of the contact's group
            print(contact.groupName)
            
            contacts.append(Contact(category: contact.groupName, firstName: contact.givenName, lastName: contact.familyName, birthday: contact.birthday))
        })
    }
    catch {
        print("Error")
    }
    
    return contacts
}