Flutter seems to skip the FutureBuilder() method

Question

I'm not able to read data from Firebase Firestore.

Flutter seems to skip the 'future builder' method. I'm not getting any error messages, it just seems like Flutter is skipping the code for FutureBuilder() method

import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:doctor_app/data/data.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:flutter/material.dart';

class DatabaseManager {

  final user = FirebaseAuth.instance.currentUser;
  CollectionReference users = 
  FirebaseFirestore.instance.collection('users');
  
  // here method GetUserData is called from another file
  Future<void> GetUserData() async {
    var documentId = user!.email;
    print("in getuserdata");
    FutureBuilder<DocumentSnapshot>(
      future: users.doc(documentId).get(),
      builder:
      (BuildContext context, AsyncSnapshot<DocumentSnapshot> snapshot) {
        print("in builder");
        if (snapshot.hasError) {
          print("Something went wrong");
        }

        if (snapshot.hasData && !snapshot.data!.exists) {
          print("Document does not exist");
        }

        if (snapshot.connectionState == ConnectionState.done) {
          print("in connection");
          Map<String, dynamic> data =
              snapshot.data!.data() as Map<String, dynamic>;
          fullname = data['FullName'];
          gender = data['Gender'];
          dob = data['Dob'];
          number = data['Number'];
        }

        return Text("loading");
      },
    );
    print("at connection end");
  }