Почему при шифровании AES результат отличается от того который выдают сервисы

Использую код

namespace Cryptography
{
    /// <summary>
    /// Static class help work crypto hashes
    /// </summary>
    public static class Crypto
    {
        #region MD5
        /// <summary>
        /// Calculate MD5 hash
        /// </summary>
        /// <param name="phrase"></param>
        /// <returns></returns>
        public static string HashMD5(string phrase)
        {
            if (phrase == null)
                return null;
            var encoder = new UTF8Encoding();
            var md5Hasher = new MD5CryptoServiceProvider();
            var hashedDataBytes = md5Hasher.ComputeHash(encoder.GetBytes(phrase));
            return ByteArrayToHexString(hashedDataBytes);
        }

        #endregion

        #region SHA
        /// <summary>
        /// Calculate SHA hash
        /// </summary>
        /// <param name="phrase"></param>
        /// <returns></returns>
        public static string HashSHA1(string phrase)
        {
            if (phrase == null)
                return null;
            var encoder = new UTF8Encoding();
            var sha1Hasher = new SHA1CryptoServiceProvider();
            var hashedDataBytes = sha1Hasher.ComputeHash(encoder.GetBytes(phrase));
            return ByteArrayToHexString(hashedDataBytes);
        }
        /// <summary>
        /// Calculate SHA256 hash
        /// </summary>
        /// <param name="phrase"></param>
        /// <returns></returns>
        public static string HashSHA256(string phrase)
        {
            if (phrase == null)
                return null;
            var encoder = new UTF8Encoding();
            var sha256Hasher = new SHA256CryptoServiceProvider();
            var hashedDataBytes = sha256Hasher.ComputeHash(encoder.GetBytes(phrase));
            return ByteArrayToHexString(hashedDataBytes);
        }
        /// <summary>
        /// Calculate SHA384 hash
        /// </summary>
        /// <param name="phrase"></param>
        /// <returns></returns>
        public static string HashSHA384(string phrase)
        {
            if (phrase == null)
                return null;
            var encoder = new UTF8Encoding();
            var sha384Hasher = new SHA384CryptoServiceProvider();
            var hashedDataBytes = sha384Hasher.ComputeHash(encoder.GetBytes(phrase));
            return ByteArrayToHexString(hashedDataBytes);
        }
        /// <summary>
        /// Calculate SHA512 hash
        /// </summary>
        /// <param name="phrase"></param>
        /// <returns></returns>
        public static string HashSHA512(string phrase)
        {
            if (phrase == null)
                return null;
            var encoder = new UTF8Encoding();
            var sha512Hasher = new SHA512CryptoServiceProvider();
            var hashedDataBytes = sha512Hasher.ComputeHash(encoder.GetBytes(phrase));
            return ByteArrayToHexString(hashedDataBytes);
        }

        #endregion

        #region AES
        /// <summary>
        /// Encrypt AES
        /// </summary>
        /// <param name="phrase"></param>
        /// <param name="key"></param>
        /// <param name="hashKey"></param>
        /// <returns></returns>
        public static string EncryptAES(string phrase, string key, bool hashKey = true)
        {
            if (phrase == null || key == null)
                return null;

            var keyArray = HexStringToByteArray(hashKey ? HashMD5(key) : key);
            var toEncryptArray = Encoding.UTF8.GetBytes(phrase);
            byte[] result;

            using (var aes = new AesCryptoServiceProvider
            {
                Key = keyArray,
                Mode = CipherMode.ECB,
                Padding = PaddingMode.PKCS7
            })
            {
                var cTransform = aes.CreateEncryptor();
                result = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
                aes.Clear();
            }
            return ByteArrayToHexString(result);
        }
        /// <summary>
        /// Decrypt AES
        /// </summary>
        /// <param name="hash"></param>
        /// <param name="key"></param>
        /// <param name="hashKey"></param>
        /// <returns></returns>
        public static string DecryptAES(string hash, string key, bool hashKey = true)
        {
            if (hash == null || key == null)
                return null;

            var keyArray = HexStringToByteArray(hashKey ? HashMD5(key) : key);
            var toEncryptArray = HexStringToByteArray(hash);

            var aes = new AesCryptoServiceProvider
            {
                Key = keyArray,
                Mode = CipherMode.ECB,
                Padding = PaddingMode.PKCS7
            };

            var cTransform = aes.CreateDecryptor();
            var resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

            aes.Clear();
            return Encoding.UTF8.GetString(resultArray);
        }

        #endregion

        #region 3DES
        /// <summary>
        /// Encrypt 3DES
        /// </summary>
        /// <param name="phrase"></param>
        /// <param name="key"></param>
        /// <param name="hashKey"></param>
        /// <returns></returns>
        public static string EncryptTripleDES(string phrase, string key, bool hashKey = true)
        {
            var keyArray = HexStringToByteArray(hashKey ? HashMD5(key) : key);
            var toEncryptArray = Encoding.UTF8.GetBytes(phrase);

            var tdes = new TripleDESCryptoServiceProvider
            {
                Key = keyArray,
                Mode = CipherMode.ECB,
                Padding = PaddingMode.PKCS7
            };

            var cTransform = tdes.CreateEncryptor();
            var resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

            tdes.Clear();
            return ByteArrayToHexString(resultArray);
        }
        /// <summary>
        /// Decrypt DES
        /// </summary>
        /// <param name="hash"></param>
        /// <param name="key"></param>
        /// <param name="hashKey"></param>
        /// <returns></returns>
        public static string DecryptTripleDES(string hash, string key, bool hashKey = true)
        {
            var keyArray = HexStringToByteArray(hashKey ? HashMD5(key) : key);
            var toEncryptArray = HexStringToByteArray(hash);

            var tdes = new TripleDESCryptoServiceProvider
            {
                Key = keyArray,
                Mode = CipherMode.ECB,
                Padding = PaddingMode.PKCS7
            };

            var cTransform = tdes.CreateDecryptor();
            var resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

            tdes.Clear();
            return Encoding.UTF8.GetString(resultArray);
        }

        #endregion

        #region Helpers
        /// <summary>
        /// Convert byte array to hex string
        /// </summary>
        /// <param name="inputArray"></param>
        /// <returns></returns>
        internal static string ByteArrayToHexString(byte[] inputArray)
        {
            if (inputArray == null)
                return null;
            var o = new StringBuilder("");
            for (var i = 0; i < inputArray.Length; i++)
                o.Append(inputArray[i].ToString("X2"));
            return o.ToString();
        }
        /// <summary>
        /// Convert hex string to byte array
        /// </summary>
        /// <param name="inputString"></param>
        /// <returns></returns>
        internal static byte[] HexStringToByteArray(string inputString)
        {
            if (inputString == null)
                return null;

            if (inputString.Length == 0)
                return new byte[0];

            if (inputString.Length%2 != 0)
                throw new Exception(
                    "Hex strings have an even number of characters and you have got an odd number of characters!");

            var num = inputString.Length/2;
            var bytes = new byte[num];
            for (var i = 0; i < num; i++)
            {
                var x = inputString.Substring(i*2, 2);
                try
                {
                    bytes[i] = Convert.ToByte(x, 16);
                }
                catch (Exception ex)
                {
                    throw new Exception("Part of your \"hex\" string contains a non-hex value.", ex);
                }
            }
            return bytes;
        }

        #endregion
    }
}

string result = Cryptography.Crypto.EncryptAES(phrase, key, true);
return result;

Вместо того чтобы выдавать значения вида U2FsdGVkX19GaqJHnsJqdoO3sgBh527zN0y0LJ0i71s=

Получаю результат 7B81E6BC019789E585549748FA2600EF Что я делаю не так?