Android Studio sqlite has no column error

I'm trying to implement a sqlite database for my code to save basic variables. However, when running on the emulator, I get a no column error. Any insight would be appreciated. The error:

 (1) table reg_info has no column named user_pass
  04-08 00:28:35.402    3133-3133/com.example.cowman897.sqlitedatabase E/SQLiteDatabase﹕ Error inserting user_pass=ghd user_ass=ggg user_name=sd
android.database.sqlite.SQLiteException: table reg_info has no column named user_pass (code 1): , while compiling: INSERT INTO reg_info(user_pass,user_ass,user_name) VALUES (?,?,?)

My code is as follows:

import android.provider.BaseColumns;


public class TableData {
public TableData()
{

}

public static abstract class TableInfo implements BaseColumns
{
    public static final String USER_NAME = "user_name";
    public static final String USER_PASS = "user_pass";
    public static final String USER_ASS = "user_ass";
    public static final String DATABASE_NAME = "user_info";
    public static final String TABLE_NAME = "reg_info";


}

}

public class DatabaseOperations extends SQLiteOpenHelper {
public static final int database_version =3;
public String CREATE_QUERY = "create table " + TableData.TableInfo.TABLE_NAME + " (" + null + " integer primary key autoincrement, " +  TableData.TableInfo.USER_NAME + " text not null, " + TableData.TableInfo.USER_PASS + " text not null, " + TableData.TableInfo.USER_ASS+ " text not null);";

public DatabaseOperations(Context context)
{
   super(context, TableData.TableInfo.DATABASE_NAME, null, database_version);
    Log.d("Database operations", "Database Created");
}
@Override
public void onCreate(SQLiteDatabase sdb) {
    sdb.execSQL(CREATE_QUERY);
    Log.d("Database operations", "Table Created");

}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

}
public void putInformation(DatabaseOperations dop, String name, String pass, String ass )
{
  SQLiteDatabase SQ = dop.getWritableDatabase();
    ContentValues cv = new ContentValues();
    cv.put(TableData.TableInfo.USER_NAME, name);
    cv.put(TableData.TableInfo.USER_PASS, pass);
    cv.put(TableData.TableInfo.USER_ASS, ass);
    long k = SQ.insert(TableData.TableInfo.TABLE_NAME, null, cv );
    Log.d("Database operations", "One raw inserted");

}

}

and the activity is just

public class MainActivity extends ActionBarActivity {
Button sub;
String Class,Date,Assignment;
EditText Class_Field,Date_Field,Assignment_Field;
Context ctx = this;

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

    sub = (Button)findViewById(R.id.button);
    Class_Field = (EditText)findViewById(R.id.editText);
    Date_Field = (EditText)findViewById(R.id.editText2);
    Assignment_Field = (EditText)findViewById(R.id.editText3);

    sub.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
        Class = Class_Field.getText().toString();
        Date = Date_Field.getText().toString();
        Assignment = Assignment_Field.getText().toString();
        DatabaseOperations DB = new DatabaseOperations(ctx);
        DB.putInformation(DB, Class, Date, Assignment);
        Toast.makeText(getBaseContext(), "Assignment Added", Toast.LENGTH_LONG).show();
        finish();

        }
    });
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
}

}

Any help would be appreciated.