Android studio 如何从SQLite中的特定数据库中删除表？

我有一个应用程序，我正在创建，我希望能够在其中输入用户用户名，然后单击删除，然后它将删除该特定用户的所有数据。但到目前为止，当我出于某种原因这样做时，它向我展示了“数据未被删除”的Toast消息，无论发生什么。如果有人知道我在代码中哪里出错了，那么任何帮助都会很棒

删除类：

public class Remove extends AppCompatActivity {

DatabaseHelperUser myDb;

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

    final EditText etUser = findViewById(R.id.editTextUser);
    myDb = new DatabaseHelperUser(this);

    Integer deletedRows = myDb.deleteData(etUser.getText().toString());
    if(deletedRows > 0){
        Toast.makeText(getApplicationContext(), "Data Deleted", Toast.LENGTH_LONG).show();}
    else{
        Toast.makeText(getApplicationContext(), "Data has not been Deleted", Toast.LENGTH_LONG).show();}

}

}

DatabaseHelperUser类：

public class DatabaseHelperUser extends SQLiteOpenHelper {

public static final String DATABASE_NAME = "User.db";
public static final String TABLE_NAME = "User_table";
public static final String COL1 = "UserNum";
public static final String COL2 = "UserName";
public static final String COL3 = "Password";
public static final String COL4 = "BirthDate";
public static final String COL5 = "Phone";
public static final String COL6 = "Address";


public  DatabaseHelperUser(Context context){
    super(context, DATABASE_NAME, null, 1);
}


@Override
public void onCreate(SQLiteDatabase db) {

    db.execSQL("create table " + TABLE_NAME + " (UserNum TEXT,UserName Text,Password Text,BirthDate Text,Phone Text,Address Text)");

}

@Override
public void onUpgrade(SQLiteDatabase db, int i, int i1) {

    db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
    onCreate(db);
}
public Cursor getData(){
    SQLiteDatabase db = this.getWritableDatabase();
    Cursor res = db.rawQuery("select * from " + TABLE_NAME, null);
    return res;
}
public Integer deleteData(String UserName){
    SQLiteDatabase db = this.getWritableDatabase();
    return db.delete(TABLE_NAME, "UserName = ?", new String[] {UserName});

}

}