错误：未连接适配器；跳过布局和复制

Question

我在RecyclerView中有一个错误。 当我转到收到的视图之一，然后按“后退”按钮时，我的RecyclerView就被复制了。也就是说，重新显示收到的视图

public class MainActivity extends AppCompatActivity implements FirebaseAuth.AuthStateListener {

private List<AutoPost> postList;
private PostListAdapter postListAdapter;
private RecyclerView listPost;

private DocumentSnapshot lastVisible;
private Boolean firstLoad = true;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    listPost = findViewById(R.id.list_post);
    listPost.setHasFixedSize(true);
    listPost.setLayoutManager(new LinearLayoutManager(this));
    postList = new ArrayList<>();
    postListAdapter = new PostListAdapter(getApplicationContext(), postList);
    listPost.setAdapter(postListAdapter);
    postListAdapter.notifyDataSetChanged();
}

@Override
public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
    if(firebaseAuth.getCurrentUser() == null) {
        sendUserToLogin();
        return;
    }
    listPost.addOnScrollListener(new RecyclerView.OnScrollListener() {
        @Override
        public void onScrolled(@NonNull RecyclerView recyclerView, int dx, int dy) {
            super.onScrolled(recyclerView, dx, dy);
            Boolean countBottom = !recyclerView.canScrollVertically(1);
            if(countBottom){
                loadMorePosts();
            }
        }
    });
    Query firstQuery = firebaseFirestore.collection("posts")
            .orderBy("time", Query.Direction.DESCENDING)
            .limit(4);
    firstQuery.addSnapshotListener(this, new EventListener<QuerySnapshot>() {
        @Override
        public void onEvent(@Nullable QuerySnapshot queryDocumentSnapshots, @Nullable FirebaseFirestoreException e) {
            if(firstLoad) {
                lastVisible = queryDocumentSnapshots.getDocuments().get(queryDocumentSnapshots.size() -1);
            }
            for(DocumentChange doc: queryDocumentSnapshots.getDocumentChanges()) {
                if(doc.getType() == DocumentChange.Type.ADDED){
                    String docID = doc.getDocument().getId();
                    AutoPost posts = doc.getDocument().toObject(AutoPost.class).withId(docID);
                    if(firstLoad) {
                        postList.add(posts);
                    } else {
                        postList.add(0, posts);
                    }
                    postListAdapter.notifyDataSetChanged();
                }
            }
            firstLoad = false;
        }
    });
}

public void onResume() {
    super.onResume();
    listPost.setAdapter(postListAdapter);
}

public void loadMorePosts() {
    Query nextQuery = firebaseFirestore.collection("posts")
            .orderBy("time", Query.Direction.DESCENDING)
            .startAfter(lastVisible)
            .limit(4);
    nextQuery.addSnapshotListener(new EventListener<QuerySnapshot>() {
        @Override
        public void onEvent(@Nullable QuerySnapshot queryDocumentSnapshots, @Nullable FirebaseFirestoreException e) {
            if(!queryDocumentSnapshots.isEmpty()) {
                lastVisible = queryDocumentSnapshots.getDocuments().get(queryDocumentSnapshots.size() -1);
                for(DocumentChange doc: queryDocumentSnapshots.getDocumentChanges()) {
                    if(doc.getType() == DocumentChange.Type.ADDED){
                        String docID = doc.getDocument().getId();
                        AutoPost posts = doc.getDocument().toObject(AutoPost.class).withId(docID);
                        postList.add(posts);

                        postListAdapter.notifyDataSetChanged();
                    }
                }
            }
        }
    });
}

}

我没有从适配器添加代码，只是因为我不确定其中是否有错误。 而且我还在一个Activity中使用了两个RecyclerView，这不是错误吗？

哪里出了错？