column ' content ' does not exist

I am using sqliteOpenHelper class for sqlite. I am learning a android book for concepts. Everything is same as in book code. But in my case app crash and showing error.Please help me for resolve this problem. In logcat Column content does not exist. When i run app on device then app crash and logcat showing this

Caused by: java.lang.IllegalArgumentException: column ' content ' does not exist

at com.example.remindersapp.ReminderSimpleCursorAdapter.<init>(ReminderSimpleCursorAdapter.java:13)
        at com.example.remindersapp.RemindersActivity.onCreate(RemindersActivity.java:41)

RemindersActivity.java

package com.example.remindersapp;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

import android.database.Cursor;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ArrayAdapter;
import android.widget.ListView;

public class RemindersActivity extends AppCompatActivity {
    private ListView mlistView;
    private RemindersDbAdapter remindersDbAdapter;
    private ReminderSimpleCursorAdapter reminderSimpleCursorAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_reminders);
        mlistView = (ListView) findViewById(R.id.reminder_listView);
        mlistView.setDivider(null);
        remindersDbAdapter = new RemindersDbAdapter(this);
        remindersDbAdapter.open();
        if (savedInstanceState == null) {
            //clear all data
            remindersDbAdapter.deleteAllReminders();
            //add some data
            insertSomeReminders();

        }

        Cursor cursor = remindersDbAdapter.fetchAllReminders();
        //from columns defined in the db
        String[] from = new String[]{remindersDbAdapter.COL_CONTENT};

        //to the ids of views in the layout
        int[] to = new int[]{R.id.row_text};
        reminderSimpleCursorAdapter = new ReminderSimpleCursorAdapter(
                RemindersActivity.this,
                //the layout of the row
                R.layout.reminders_row,
                cursor,
                //from columns defined in the db
                from,
                //to the ids of views in the layout
                to,
                //flag - not used
                0);

//        ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(
//                this,
//                R.layout.reminders_row,
//                R.id.row_text,
//                new String[]{"fisrt record", "second record", "third record"
//                        , "fourth record", "fifth record"});
        mlistView.setAdapter(reminderSimpleCursorAdapter);
        //Adapter is a
        //special Java class defined as part of the Android SDK that functions as the Controller in
        //the Model-View-Controller relationship
    }

    private void insertSomeReminders() {
        remindersDbAdapter.createReminder("Learn android Development", true);
        remindersDbAdapter.createReminder("data Mining Assignment on 23-04-21", false);
        remindersDbAdapter.createReminder("Networking Assignment on 25-04-2021", false);
        remindersDbAdapter.createReminder("English Assignment on 30-04-2o21", false);
        //  //There are several calls to the createReminder() method, each taking a String value
        //with the reminder text and a boolean value flagging the reminder as important. We set
        //a few values to true to provide a good visual effect.
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.reminder_menu, menu);
        return true;

    }

    @Override
    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
        switch (item.getItemId()) {
            case R.id.action_new:
                //create new reminder
                Log.d(getLocalClassName(), "create new reminder");
                return true;
            case R.id.action_exit:
                finish();
                return true;
            default:
                return false;
        }

    }
}

ReminderSimpleCursorAdater.java

package com.example.remindersapp;

import android.content.Context;
import android.database.Cursor;
import android.view.View;
import android.view.ViewGroup;
import android.widget.SimpleCursorAdapter;

import androidx.recyclerview.widget.RecyclerView;

public class ReminderSimpleCursorAdapter extends SimpleCursorAdapter {
    public ReminderSimpleCursorAdapter(Context context, int layout, Cursor c, String[] from, int[] to, int i) {
        super(context, layout, c, from, to,i);
    }
    ////to use a viewholder, you must override the following two methods and define a ViewHolder class




    @Override
    public View newView(Context context, Cursor cursor, ViewGroup parent) {

        return super.newView(context, cursor, parent);
    }

    @Override
    public void bindView(View view, Context context, Cursor cursor) {
        super.bindView(view, context, cursor);
        ViewHolder holder=(ViewHolder)view.getTag();
        if (holder == null){
            holder=new ViewHolder();
            holder.colImp=cursor.getColumnIndexOrThrow(RemindersDbAdapter.COL_IMPORTANT);
            holder.listTab=view.findViewById(R.id.row_tab);
            view.setTag(holder);
        }
        if (cursor.getInt(holder.colImp) > 0){
            holder.listTab.setBackgroundColor(context.getResources().getColor(R.color.orange));
        }else {
            holder.listTab.setBackgroundColor(context.getResources().getColor(R.color.txt_color));
        }
    }
    //Here you see an example of the ViewHolder pattern. This is a well-known Android pattern
    //in which a small ViewHolder object is attached as a tag on each view. This object adds
    //decoration for View objects in the list by using values from the data source, which in this
    //example is the Cursor. The ViewHolder is defined as a static inner class with two instance
    //variables, one for the index of the Important table column and one for the row_tab view you
    //defined in the layout.
    static class ViewHolder{
        //store the column index
        int colImp;
        //store the view
        View listTab;
    }
}

RemindersDbAdapter.java

package com.example.remindersapp;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;

public class RemindersDbAdapter {

    //these are the column names
    public static final String COL_ID = "_id";
    public static final String COL_CONTENT =  "content" ;
    public static final String COL_IMPORTANT = "important";

    //these are the corresponding indices

    private static final int INDEX_ID = 0;
    private static final int INDEX_CONTENT = INDEX_ID + 1;
    private static final int INDEX_IMPORTANT = INDEX_ID + 2;

    //used for logging
    private static final String TAG = "RemindersDbAdapter";

    private DatabaseHelper mDbHelper;
    private SQLiteDatabase mDb;

    private static final String DATABASE_NAME = "dba_reminder";
    private static final String TABLE_NAME = "table_reminder";
    private static final int DATABASE_VERSION = 3;

    private final Context mCtx;

    ////SQL statement used to create the database
    private static final String DATABSE_CREATE = "CREATE TABLE if not exists " + TABLE_NAME + " ( " +
            COL_ID + " INTEGER PRIMARY KEY autoincrement, " +
            COL_CONTENT + " TEXT, " +
            COL_IMPORTANT + "INTEGER );";

    public RemindersDbAdapter(Context Ctx) {
        //The constructor saves an instance of Context, which is passed to DatabaseHelper
        this.mCtx = Ctx;
    }

//The open()
//method initializes the helper and uses it to get an instance of the database,

    public void open() throws SQLException {
        mDbHelper = new DatabaseHelper(mCtx);
        mDb = mDbHelper.getWritableDatabase();
    }

    //the close()
    //method uses the helper to close the database.
    public void close() throws SQLException {
        if (mDbHelper != null) {
            mDbHelper.close();
        }
    }
    //CREATE
//note that the id will be created for you automatically

    public void createReminder(String name, boolean important) {
        ContentValues values = new ContentValues();
        values.put(COL_CONTENT, name);
        values.put(COL_IMPORTANT, important ? 1 : 0);
        mDb.insert(TABLE_NAME, null, values);

    }
    ////overloaded to take a reminder

    public long createReminder(Reminder reminder) {
        ContentValues values = new ContentValues();
        values.put(COL_CONTENT, reminder.getmContent()); //Contact name
        values.put(COL_IMPORTANT, reminder.getImportant()); //Contact phone number

        //// Inserting Row
        return mDb.insert(TABLE_NAME, null, values);
    }
    //READ

    public Reminder fetchReminderById(int id) {
        Cursor cursor = mDb.query(TABLE_NAME,
                new String[]{COL_ID, COL_CONTENT, COL_IMPORTANT},
                COL_ID + " =? ",
                new String[]{String.valueOf(id)},
                null, null, null, null);
        if (cursor != null)
            cursor.moveToFirst();
        return new Reminder(
                cursor.getInt(INDEX_ID),
                cursor.getString(INDEX_CONTENT),
                cursor.getInt(INDEX_IMPORTANT));


    }

    public Cursor fetchAllReminders() {

        Cursor mcursor = mDb.query(TABLE_NAME, new String[]{COL_ID, COL_CONTENT, COL_IMPORTANT},
                null, null, null, null, null);
        if (mcursor != null) {
            mcursor.moveToFirst();
        }
        return mcursor;
    }

    //UPDATE
    public void updateReminder(Reminder reminder) {
        ContentValues values = new ContentValues();
        values.put(COL_CONTENT, reminder.getmContent());
        values.put(COL_IMPORTANT, reminder.getImportant());
        mDb.update(TABLE_NAME, values, COL_ID + " =? ", new String[]{String.valueOf(reminder.getmId())});
    }
    //DELETE
    public void deleteReminderById(int id){
        mDb.delete(TABLE_NAME,COL_ID + "=?", new String[]{String.valueOf(id)});
    }
    public void deleteAllReminders(){
        mDb.delete(TABLE_NAME,null,null);
    }

//sqlite open helper

    private static class DatabaseHelper extends SQLiteOpenHelper {

        public DatabaseHelper(Context context) {
            super(context, DATABASE_NAME, null, DATABASE_VERSION);
        }

        @Override
        public void onCreate(SQLiteDatabase db) {
            Log.w(TAG, DATABSE_CREATE);
            db.execSQL(DATABSE_CREATE);

        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            Log.w(TAG, "Upgrading database from version " + oldVersion + "to " + newVersion + ",which will destroy all old data");
            db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
            onCreate(db);


        }

        @Override
        public void onOpen(SQLiteDatabase db) {
            super.onOpen(db);
            onCreate(db);
        }
    }

}

column ' content ' does not exist

Remove the whitespace around content in COL_CONTENT.