How to delete all data HistoryTable have time older than 30days in SQLite Android

CREATE TABLE
public static void createTable(SQLiteDatabase db){
String sql = "CREATE TABLE " + TABLE_HISTORY + " ("
+ COL_ID + " INTEGER PRIMARY KEY NOT NULL, "
+ COL_TITLE + " TEXT, "
+ COL_MEDIA_NAME + " TEXT, "
+ COL_IMAGE_URL + " TEXT, "
+ COL_URL + " TEXT, "
+ COL_CREATED_AT + " INTEGER NOT NULL DEFAULT 0, "
+ COL_UPDATED_AT + " INTEGER NOT NULL DEFAULT 0 "
+ ")";
db.execSQL(sql);
}

INSERT TABLE

 public static long insertTableHistory(DatabaseDAO db, int mId, String title, String mediaName, String imageUrl, String url) {
    SQLiteDatabase database = db.getWritableDatabase();
    String sql =
            "INSERT INTO " + TABLE_HISTORY + " ("
                    + COL_ID + ", "
                    + COL_TITLE + ", "
                    + COL_MEDIA_NAME + ", "
                    + COL_IMAGE_URL + ", "
                    + COL_URL + ", "
                    + COL_CREATED_AT + ","
                    + COL_UPDATED_AT +
                    ")"
                    + " VALUES (?, ?, ?, ?, ?, ?, ?, ?)";
SQLiteStatement statement = database.compileStatement(sql);
    long id = -1;
    try {
        database.beginTransaction();
        statement.clearBindings();
        statement.bindLong(1, mId);
        statement.bindString(2, title);
        statement.bindString(3, mediaName);
        statement.bindString(4, imageUrl);
        statement.bindString(5, url);
        statement.bindLong(6, System.currentTimeMillis());
        statement.bindLong(7, System.currentTimeMillis());
        id = statement.executeInsert();
        database.setTransactionSuccessful();

    } catch (Exception e) {
        database.endTransaction();
    } finally {
        database.endTransaction();
    }
    return id;
}

I try it But it not working.

public static void deleteDataOlderThan30Days(DatabaseDAO databaseDAO) {

    String sql = "DELETE FROM " + TABLE_HISTORY + " WHERE " + COL_CREATED_AT + "<= date('now','-30 day')";
    SQLiteDatabase database = databaseDAO.getWritableDatabase();
    database.execSQL(sql);
}

How to I can delete all data at HistotyTable older than 30days?
Please. Help me!