recyclerview item mishap(undesirable behaviour) in android studio

I have a recycler view with a list of items and each of those items have checkboxes attached to them. When a checkbox is checked, it behaves properly and there is no problem with unwanted items getting checked. But when a checked item is deleted, then the unwanted item gets checked.

My Adapter Class :

public class TaskAdapter extends RecyclerView.Adapter<TaskAdapter.TaskHolder> {
private static List<Task> tasks = new ArrayList<>();
private static OnItemClickListener listener;
private static TaskAdapter adapter = new TaskAdapter();


@NonNull

@Override
public TaskHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
    View itemView = LayoutInflater.from(parent.getContext())
            .inflate(R.layout.task_item, parent, false);
    return new TaskHolder(itemView);
}

@Override
public void onBindViewHolder(@NonNull TaskHolder holder, int position) {
    Task currentTask = tasks.get(position);
    holder.a_tname.setText(currentTask.getTname());
    holder.a_tdate.setText(currentTask.getTDate());
    holder.a_ttime.setText(currentTask.getTTime());
    holder.a_tprior.setText(currentTask.getTprior());
    holder.bind(tasks.get(position));
   holder.bind2(tasks.get(position));

}
@Override
public int getItemCount() {
    return tasks.size();
}
public void setTasks(List<Task> tasks) {
    this.tasks = tasks;
    Collections.sort( tasks, Task.comparepriority);
    notifyDataSetChanged();
}
public Task getTaskAt(int position){
    return tasks.get(position);
}

 class TaskHolder extends RecyclerView.ViewHolder  {
    private final TextView a_tname;
    private final TextView a_tdate;
    private  final TextView a_ttime;
    private final TextView a_tprior;
    ImageView priorityIndicator;
    CheckBox checkbox;


    public TaskHolder(View itemView) {
        super(itemView);
        a_tname = itemView.findViewById(R.id.a_tname);
        a_tdate=itemView.findViewById(R.id.a_tdate);
        a_ttime = itemView.findViewById(R.id.a_ttime);
        a_tprior = itemView.findViewById(R.id.a_tprior);
        priorityIndicator = itemView.findViewById(R.id.priorityIndicator);
        checkbox = itemView.findViewById(R.id.checkbox);




        itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                int position = getAdapterPosition();
                if(listener!=null&&position!=RecyclerView.NO_POSITION){
                    listener.onItemClick(tasks.get(position));
                }
            }
        });

    }

    private void bind(Task task){
        int drawableId;int red = R.color.red;int yellow = R.color.yellow;int green = R.color.green;
        int color1 = ContextCompat.getColor(a_tprior.getContext(), red);
        int color2 = ContextCompat.getColor(a_tprior.getContext(),yellow);
        int color3 = ContextCompat.getColor(a_tprior.getContext(),green);
        switch(task.t_prior){
            case "1": drawableId = R.drawable.ic_baseline_priority_high_24;
            a_tprior.setTextColor(color1);
            break;
            case "2": drawableId = R.drawable.ic_baseline_priority_middle_24;
            a_tprior.setTextColor(color2);
            break;
            case "3" : drawableId = R.drawable.ic_baseline_low_priority_24;
            a_tprior.setTextColor(color3);
            break;
            default: drawableId = R.drawable.ic_baseline_crop_square_24;
        }
        priorityIndicator.setImageDrawable(ContextCompat.getDrawable(priorityIndicator.getContext(),drawableId));
    }

    public void bind2(Task task){
        final boolean[] checked = {true};
        checkbox.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(checkbox.isChecked()) {
                    String pos = Integer.valueOf(getAdapterPosition()).toString();
                    PreferenceManager.getDefaultSharedPreferences(checkbox.getContext()).edit().
                            putBoolean("checkbox" + pos , checked[0]).apply();
                    Toast.makeText(checkbox.getContext(), "Way to go! Now swipe to delete", Toast.LENGTH_LONG).show();
                }
                else  {
                    checked[0] =false;
                    String pos = Integer.valueOf(getAdapterPosition()).toString();
                    PreferenceManager.getDefaultSharedPreferences(checkbox.getContext()).edit().
                            putBoolean("checkbox" + pos, checked[0]).apply();
                }
            }
        }); String pos = Integer.valueOf(getAdapterPosition()).toString();
        boolean cb = PreferenceManager.getDefaultSharedPreferences(checkbox.getContext()).getBoolean
                ("checkbox" + pos, false);
        checkbox.setChecked(cb);
    }

 }
public interface  OnItemClickListener {
    void onItemClick(Task ta);
}
public void setOnItemClickListener(OnItemClickListener listener){
    this.listener = listener;
}

}

My code to delete in HomeFragment.java -

  new ItemTouchHelper(new ItemTouchHelper.SimpleCallback(0,
            ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT) {
        @Override
        public boolean onMove(@NonNull RecyclerView recyclerView, @NonNull
                RecyclerView.ViewHolder viewHolder, @NonNull  RecyclerView.ViewHolder target) {
            return false;
        }

        @Override
        public void onSwiped(@NonNull  RecyclerView.ViewHolder viewHolder, int direction) {
            int position = viewHolder.getAdapterPosition();
            new AlertDialog.Builder(getActivity())
                    .setMessage("Do you want to delete this task?")
                    .setPositiveButton("Delete", ((dialog, which) ->
                            taskViewmodel.delete(adapter.getTaskAt(viewHolder.getAdapterPosition()))))
                    .setNegativeButton("Cancel", ((dialog, which) -> adapter.notifyItemChanged(position)))
                    .setOnCancelListener(dialog -> adapter.notifyItemChanged(position))
                    .create().show();


        }
    }).attachToRecyclerView(recyclerView);

May i know what changes should i make to rectify this problem? Thankyou