Flutter, Rooted Device. File Copy Permission denied

I am using the root_access and permission_handler packages in a Flutter app to copy a file from the data folder to the storage. Although all required permissions are granted, I receive the following error: OS Error: Permission denied, errno = 13. This occurs on an Android device that is rooted and running Flutter version 3.7.11. and an Android SDK version 33.0.2. In the AndroidManifest File, I added uses-permission. I am able to copy from storage to storage without any issues.

The code snippet that causes the error is as follows, as it attempts to copy file /data/file.txt to /storage/emulated/0/documents/file.txt:

import 'dart:async';
import 'dart:io';
import 'package:permission_handler/permission_handler.dart';
import 'package:root_access/root_access.dart';

Future<void> copyrootfile() async {
    var status = await Permission.storage.status;
    var status2 = await Permission.accessMediaLocation.status;
    var status3 = await Permission.manageExternalStorage.status;
    if (!status.isGranted) {
      await Permission.storage.request();
    }
    if (!status2.isGranted) {
      await Permission.accessMediaLocation.request();
    }
    if (!status3.isGranted) {
      await Permission.manageExternalStorage.request();
    }
    await RootAccess.requestRootAccess;

    var rootFileText = "/data/file.txt";
    final rootFile = File(rootFileText);

    var copyTo = '/storage/emulated/0/documents/file.txt';
    if(rootFile.existsSync()){
        await rootFile.copy(copyTo);
    }
}

I believe I have included all necessary permissions, so I am not sure why the copy operation is failing. Any suggestions on how to fix this issue?

Update
I got this error message

E/flutter (27371): [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: FileSystemException: Cannot copy file to '/storage/emulated/0/Documents/file.txt', path = '/data/file.txt' (OS Error: Permission denied, errno = 13)
E/flutter (27371): #0      _checkForErrorResponse (dart:io/common.dart:42:9)
E/flutter (27371): #1      _File.copy.<anonymous closure> (dart:io/file_impl.dart:339:7)
E/flutter (27371): <asynchronous suspension>
E/flutter (27371): #2      _MyHomePageState.copyrootfile (package:rootcopy/main.dart:90:7)
E/flutter (27371): <asynchronous suspension>
E/flutter (27371): #3      _MyHomePageState.build.<anonymous closure> (package:rootcopy/main.dart:130:17)
E/flutter (27371): <asynchronous suspension>

I can't find a solution when using copy function to copy file from data folder to storage. But I was able to find a solution instead.
So i used root package instead of root_access.
Package Link root.

The succesful code snippet is as follows.

  import 'dart:async';
import 'dart:io';
import 'package:permission_handler/permission_handler.dart';
import 'package:root/root.dart';
Future<void> copyrootfile() async {
bool isRooted = await Root.isRooted() ?? false;
bool isRootAvailable = await Root.isRootAvailable() ?? false;
var status = await Permission.storage.status;
var status2 = await Permission.accessMediaLocation.status;
var status3 = await Permission.manageExternalStorage.status;
if (!status.isGranted) {
await Permission.storage.request();
}
if (!status2.isGranted) {
await Permission.accessMediaLocation.request();
}
if (!status3.isGranted) {
await Permission.manageExternalStorage.request();
}
var rootFileText = "/data/file.txt";
final rootFile = File(rootFileText);
// var copyTo = '/storage/emulated/0/Documents/file.txt';
var copyToFolder = '/storage/emulated/0/Documents/';
if (rootFile.existsSync()) {
String copycmd = "cp $rootFileText $copyToFolder";
if (isRooted && isRootAvailable) {
// Check folder Exist.
final checkFolderExist = await Directory(copyToFolder).exists();
if (!checkFolderExist) {
// Create folder if not Exist.
await Directory(copyToFolder).create(recursive: true);
}
// Copy using command line.
await Root.exec(cmd: copycmd);
}
}
}