Why am I getting this error?

{
  "category" : {
    "01" : {
      "image" : "https://www.carusopizza.cz/185-large_default/prosciutto.jpg",
      "name" : "Pizza Prosciuto"
    },
    "02" : {
      "image" : "http://urgentpizza.ro/blog/wp-content/uploads/2014/06/pizza-diavola-urgentpizza1.jpg",
      "name" : "Pizza Diavolo"
    },
    "03" : {
      "image" : "https://www.carusopizza.cz/388/1047.jpg",
      "name" : "Pizza Funghi"
    }
  },
  "user" : {
    "12345" : {
      "name" : "Tiganu",
      "password" : "1234"
    }
  }
}

private void LoadMenu(){
        Query query =  FirebaseDatabase.getInstance().getReference().child("category");
        FirebaseRecyclerOptions<Category> options = new FirebaseRecyclerOptions.Builder<Category>()
                .setQuery(query, new SnapshotParser<Category>() {
                    @NonNull
                    @Override
                    public Category parseSnapshot(@NonNull DataSnapshot snapshot) {
                        return new Category(snapshot.child("image").getValue().toString(), snapshot.child("name").getValue().toString());
                    }
                }).build();
        adapter = new FirebaseRecyclerAdapter<Category, MenuViewHolder>(options) {
            @Override
            protected void onBindViewHolder(@NonNull MenuViewHolder holder, int position, @NonNull Category model) {
                holder.menuName.setText(model.getName());
                Picasso.with(getBaseContext()).load(model.getImage()).into(holder.imageView);
                final Category clickItem = model;
                holder.setItemClickListener(new ItemClickListener() {
                    @Override
                    public void onClick(View view, int position, boolean isLongClick) {
                        Toast.makeText(HomeActivity.this, "" + clickItem.getName(), Toast.LENGTH_SHORT).show();
                    }
                });
            }

            @NonNull
            @Override
            public MenuViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
                View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.activity_home, viewGroup, false);
                return new MenuViewHolder(view);
            }
        };
        recyclerView.setAdapter(adapter);
    }

package com.example.pizzaapp;

public class Category {
    private String image;
    private String name;
    public Category(){

    }
    public Category(String image, String name){
        this.image = image;
        this.name = name;
    }
    public String getName(){
        return name;
    }
    public String getImage(){
        return image;
    }
    public void setName(String name){
        this.name = name;
    }
    public void setImage(String image){
        this.image = image;
    }
}

package com.example.pizzaapp;

import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.widget.ImageView;
import android.widget.TextView;

public class MenuViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{
    public TextView menuName;
    public ImageView imageView;
    private ItemClickListener itemClickListener;
    public MenuViewHolder(View itemView){
        super(itemView);
        menuName = (TextView)itemView.findViewById(R.id.menu_name);
        imageView = (ImageView)itemView.findViewById(R.id.menu_image);
        itemView.setOnClickListener(this);
    }
    public void setItemClickListener(ItemClickListener itemClickListener){
        this.itemClickListener = itemClickListener;
    }
    @Override
    public void onClick(View view){
        itemClickListener.onClick(view, getAdapterPosition(), false);
    }
    public TextView getMenuName(){
        return menuName;
    }
    public ImageView getImageView(){
        return imageView;
    }
    public void setMenuName(TextView view){
        menuName = view;
    }
    public void setImageView(ImageView view){
        imageView = view;
    }
}

java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference
        at com.example.pizzaapp.HomeActivity$2.onBindViewHolder(HomeActivity.java:58)
        at com.example.pizzaapp.HomeActivity$2.onBindViewHolder(HomeActivity.java:55)

adapter = new FirebaseRecyclerAdapter<Category, MenuViewHolder>(options) {

holder.menuName.setText(model.getName());

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context=".HomeActivity"
    tools:showIn="@layout/app_bar_home">
    <android.support.v7.widget.RecyclerView
        android:id="@+id/recycler_menu"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scrollbars="vertical">

    </android.support.v7.widget.RecyclerView>
</android.support.constraint.ConstraintLayout>