Issue with

BankartDebit.Cs

        [Test, Explicit]
        public async Task Debit()
        {
            var request = new Debit
            {
                Currency = "EUR",
                SuccessUrl = "www.domain.si/successURL",
                ErrorUrl = "www.domain.si/errorURL",
                CancelUrl = "www.domain.si/cancelURL",
                CallbackUrl = "www.domain.si/callbackURL",
                Amount = "100.00",
                MerchantTransactionId = "12348",

            };
            var byteArray = Encoding.ASCII.GetBytes("**:**);
            DateTime timeSent = DateTime.Now;
            var httpClient = new HttpClient();

            var json = JsonConvert.SerializeObject(request);
            string hmacValue;
            using (HMACSHA512 hmac = new HMACSHA512(Encoding.UTF8.GetBytes("***")))
            {
                using (MD5 md5 = MD5.Create())
                {
                    string md5xml = BitConverter.ToString(md5.ComputeHash(Encoding.UTF8.GetBytes(json))).Replace("-", string.Empty).ToLower();
                    string[] headerData = { "POST", "application/json", md5xml, timeSent.ToUniversalTime().ToString("r"),  $"/api/v3/transaction/***/debit" };
                    var joinedHeaderData = string.Join("\n", headerData);
                    hmacValue = Convert.ToBase64String(hmac.ComputeHash(Encoding.UTF8.GetBytes(joinedHeaderData)));
                }
            }

            httpClient.DefaultRequestHeaders.Add("X-Signature", hmacValue);
            httpClient.DefaultRequestHeaders.Date = timeSent.ToUniversalTime();
            httpClient.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Basic", Convert.ToBase64String(byteArray));
            IBankartClient client = new BankartClient(httpClient);
            TransactionResponse response = await client.ProcessDebitAsync("***", request);
        }