title: Flutter Secure Storage Issues: Unable to read or write keys and values
body: <p>I am using this package to store some login credentials in a Flutter mobile application. The version I use is <strong>v5.0.2</strong>. I am not sure if I am storing or reading the value in the correct way. Does anyone know how to check it, or what am I missing or doing wrong.</p>
  <pre><code>import 'package:flutter_secure_storage/flutter_secure_storage.dart';
  
  class SecureStorage {
    final _storage = const FlutterSecureStorage();
  
    Future&lt;Map&lt;String, String&gt;&gt; _readAll() async {
      return await _storage.readAll(
          iOptions: _getIOSOptions(), aOptions: _getAndroidOptions());
    }
  
    void deleteAll() async {
      await _storage.deleteAll(
          iOptions: _getIOSOptions(), aOptions: _getAndroidOptions());
      _readAll();
    }
  
    Future&lt;String?&gt; readSecureData(String key) async {
      return await _storage.read(key: key);
    }
  
    Future&lt;void&gt; deleteSecureData(String key) async {
      return await _storage.delete(key: key);
    }
  
    void writeSecureData(String key, String value) async {
      await _storage.write(
        key: key,
        value: value,
        iOptions: _getIOSOptions(),
        aOptions: _getAndroidOptions(),
      );
    }
  
    IOSOptions _getIOSOptions() =&gt; const IOSOptions(
          accessibility: IOSAccessibility.first_unlock,
        );
  
    AndroidOptions _getAndroidOptions() =&gt; const AndroidOptions(
          encryptedSharedPreferences: true,
        );
  }
  
  final secureStorage = SecureStorage();
  </code></pre>
  <p>This is how I called the value,</p>
  <pre><code>@override
    void initState() {
      Future.delayed(Duration.zero, () async {
        final username = await secureStorage.readSecureData('username') ?? '';
        final password = await secureStorage.readSecureData('password') ?? '';
        setState(() {
          _icNoController.text = username;
          _passwordController.text = password;
        });
      });
      super.initState();
    }
  </code></pre>
  <p>And this is how I stored the value,</p>
  <pre><code>await secureStorage.writeSecureData('username', username);
  await secureStorage.writeSecureData('password', password);
  </code></pre>