Cant retrieve user data form Firebase using query : I have the following firebase structure:

    Users" : {
    "angelbreath" : {
          "PvP_Wins" : 0,
          "PvP_scores" : 0,
          "avatar" : "https://i.imgur.com/qp9gnKE.png",
          "gender" : "Male",
          "userName" : "angelbreath",
          "user_class" : "Bard",
          "user_id" : "sC8JGw6SvMUGH4Id1HwcSf6Sl5n1"
        },  

I m trying to get the data of current auth user with no luck because of null exception. After many tries i have end up with this code:

  

    private void showData() {
                DatabaseReference Users = database.getReference("Users");
                final Query userQuery = Users.orderByChild("user_id");
                final FirebaseUser user = firebaseAuth.getCurrentUser();
        
                userQuery.addListenerForSingleValueEvent(new ValueEventListener() {
                    @Override
                    public void onDataChange(DataSnapshot dataSnapshot) {
                        for(DataSnapshot post : dataSnapshot.getChildren() ){
                            if(post.child("user_id").getValue().equals(user.getUid())){
                                Log.d("Output", "Found");
                                Log.d("Output", post.getKey().toString());
        
                                userClass.setText(post.child("user_class").getValue().toString());
                                userGender.setText(post.child("gender").getValue().toString());
                            }else{
                                Log.d("Output", "Failure");
                            }
        
                            Log.d("Output", post.child("user_id").toString());
                        }
                    }
        
                    @Override
                    public void onCancelled(DatabaseError databaseError) {
        
                    }
                });

As i can understand because i m new to firebase, i have the right reference and i query the right way. I cant figure out why i get the exception.
Just in case i have the following check too :

    //Checking whether a user as already Logged In
            if(firebaseAuth.getCurrentUser()==null){
                finish();
                //Starting the User Login Activity if the user is not Logged in
                startActivity(new Intent(this,MainActivity.class));
            }

So i think i have the current user and his id, so i querry Users with the user id. What is wrong? 
I ll appriciate any help!

