diff --git a/app/src/main/java/com/example/citrusclient/views/CalendarFragment.java b/app/src/main/java/com/example/citrusclient/views/CalendarFragment.java
index 47a0b82..3dba52e 100644
--- a/app/src/main/java/com/example/citrusclient/views/CalendarFragment.java
+++ b/app/src/main/java/com/example/citrusclient/views/CalendarFragment.java
@@ -11,7 +11,6 @@
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
 
-import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
@@ -19,7 +18,6 @@
 import android.widget.Button;
 import android.widget.LinearLayout;
 import android.widget.RadioGroup;
-import android.widget.RatingBar;
 import android.widget.TableLayout;
 import android.widget.TableRow;
 import android.widget.TextView;
@@ -190,7 +188,7 @@
         scheduleViewModel.getSchedulesByMonth().observe(getViewLifecycleOwner(), new Observer<HashMap<Integer, HashMap<Integer, Schedule>>>() {
             @Override
             public void onChanged(HashMap<Integer, HashMap<Integer, Schedule>> integerHashMapHashMap) {
-                TextView curMonth = view.findViewById(R.id.month);
+                TextView curMonth = view.findViewById(R.id.Month);
                 schedules = integerHashMapHashMap;
                 updateCalendar(curMonth);
             }
@@ -201,7 +199,7 @@
             public void onChanged(HashMap<Integer, Book> integerBookHashMap) {
                 books = integerBookHashMap;
                 if(books != null) {
-                    TextView curMonth = view.findViewById(R.id.month);
+                    TextView curMonth = view.findViewById(R.id.Month);
                     if(todos != null) {
                         todos.clear();
                     } else {
@@ -220,13 +218,15 @@
         todosViewModel.getTodosByMonthLiveData().observe(getViewLifecycleOwner(), new Observer<HashMap<Integer, HashMap<Integer, Todo>>>() {
             @Override
             public void onChanged(HashMap<Integer, HashMap<Integer, Todo>> integerHashMapHashMap) {
-                TextView curMonth = view.findViewById(R.id.month);
-                for (int day:integerHashMapHashMap.keySet()){
-                    if(todos.get(day) == null){
-                        todos.put(day, new HashMap<>());
-                    }
-                    for(int todoId:integerHashMapHashMap.get(day).keySet()){
-                        todos.get(day).put(todoId, integerHashMapHashMap.get(day).get(todoId));
+                TextView curMonth = view.findViewById(R.id.Month);
+                if(integerHashMapHashMap != null && !integerHashMapHashMap.isEmpty()) {
+                    for (int day : integerHashMapHashMap.keySet()) {
+                        if (todos.get(day) == null) {
+                            todos.put(day, new HashMap<>());
+                        }
+                        for (int todoId : integerHashMapHashMap.get(day).keySet()) {
+                            todos.get(day).put(todoId, integerHashMapHashMap.get(day).get(todoId));
+                        }
                     }
                 }
                 updateCalendar(curMonth);
@@ -235,7 +235,6 @@
 
         booksViewModel.loadBooks(accountId, token);
 
-
         tableLayout =  view.findViewById(R.id.calendarlayout);
         Calendar calendar = Calendar.getInstance();
         year = calendar.get(Calendar.YEAR); //現在の年
@@ -258,10 +257,10 @@
         DayOfWeek dayOfWeek = firstDay.getDayOfWeek();
         int firstDayOfWeek = dayOfWeek.getValue();
 
-        Button nextMonth = view.findViewById(R.id.nextMonth);
-        Button prevMonth = view.findViewById(R.id.prevMonth);
+        Button nextMonth = view.findViewById(R.id.NextMonth);
+        Button prevMonth = view.findViewById(R.id.PrevMonth);
         FloatingActionButton createBook = view.findViewById(R.id.floatingActionButton);
-        TextView curMonth = view.findViewById(R.id.month);
+        TextView curMonth = view.findViewById(R.id.Month);
         curMonth.setText(year + "年" + month + "月");
 
         createBook.setOnClickListener(new View.OnClickListener() {
@@ -374,7 +373,7 @@
 
         String[][] days = calendarString(firstDayOfWeek, prevMonthDay, lastDay);
         int one = 0;
-        RadioGroup selectButton = getView().findViewById(R.id.selectButton);
+        RadioGroup selectButton = getView().findViewById(R.id.SelectButton);
 
         for(int i = 0; i < 6; i++) {
             TableRow tableRow = (TableRow) tableLayout.getChildAt(i);