Retrieving list of products from real time firebase android studio - firebase

Question

I am trying to retrieve all the products from the product structure in real time firebase. When I run the app crashes but when I comment "Product product = childSnapShot.getValue(Product.class);" it doesn't retrieve any data. Also when I try to retrieve from the Users structure it works.
Why does that happen?
public class User_products_list extends AppCompatActivity {
private ListView listView;
private FirebaseDatabase database;
private DatabaseReference myRef;
//Define Array list
private ArrayList<String> arrayList = new ArrayList<>();
// Define a ListView to display the data
private ListView listViewdata;
// Define an ArrayAdapter for the list
private ArrayAdapter<String> arrayAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.list_data);
myRef = FirebaseDatabase.getInstance().getReference();
myRef = myRef.child("Products");
listViewdata = (ListView) findViewById(R.id.list_View);
// Set the ArrayAdapter to the ListView
arrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, arrayList);
listViewdata.setAdapter(arrayAdapter);
myRef.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot snapshot) {
for(DataSnapshot childSnapShot : snapshot.getChildren()) {
Product product = childSnapShot.getValue(Product.class);
arrayList.add(product.getName());
arrayList.add(product.getDescription());
arrayAdapter.notifyDataSetChanged();
}
}
#Override
public void onCancelled(#NonNull DatabaseError error) {
}
});
}