I made a node server where i get the encrypted token for my map services, in my flutter app i decrypt it .

The thing is i wanted to protect my token from beeing to obvious inside the code but now the key is also exposed,so what i can do ?

Many guys say about flutter_secure_storage and .env but are they really secure on client side?

Here is my code :

Future<String> decryptMessage(String token) async {
  try {
    token = token.replaceAll('"', '');
    print('Encrypted token from decryptMessage function: $token');

    //Key
    var iv = encrypt.IV.fromUtf8('ASDFGHJKLASDFGHJ');
    var key = encrypt.Key.fromUtf8('ASDFGHJKLASDFGHJ');
    final encrypter = encrypt.Encrypter(encrypt.AES(
      key,
      mode: encrypt.AESMode.cbc,
      padding: null,
    ));

    // Decrypt
    var encryptedToken = encrypt.Encrypted.fromBase64(token);
    final decryptedToken = encrypter.decrypt(encryptedToken, iv: iv);

    print(decryptedToken);
    return decryptedToken;
  } catch (error) {
    throw Exception('Error occurred: $error');
  }
}