diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index ac3b892..5af478e 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -6,6 +6,7 @@ jobs:
   build-and-test:
     runs-on: ubuntu-latest
     strategy:
+      fail-fast: false
       matrix:
         dotnet-version: [ '6.0', '7.0', '8.0' ]
     
@@ -16,7 +17,7 @@ jobs:
         with:
           dotnet-version: ${{ matrix.dotnet-version }}
       - name: Install dependencies
-        run: dotnet restore
+        run: dotnet restore -p:TargetFramework=net${{ matrix.dotnet-version }}
       - name: Build
         run: dotnet build --no-restore -f net${{ matrix.dotnet-version }}
       - name: Test
diff --git a/BitPay/Client.cs b/BitPay/Client.cs
index a9f46d6..3d44734 100644
--- a/BitPay/Client.cs
+++ b/BitPay/Client.cs
@@ -316,11 +316,15 @@ public async Task<Invoice> CancelInvoiceByGuid(string refundGuid)
         ///     Request a webhook to be resent.
         /// </summary>
         /// <param name="invoiceId">Invoice ID.</param>
+        /// <param name="invoiceToken">
+        ///    The resource token for the invoiceId. 
+        ///    This token can be retrieved from the Bitpay's invoice object.
+        /// </param>
         /// <returns>Status of request</returns>
         /// <exception cref="ArgumentNullException"></exception>
-        public async Task<Boolean> RequestInvoiceWebhookToBeResent(string invoiceId)
+        public async Task<Boolean> RequestInvoiceWebhookToBeResent(string invoiceId, string invoiceToken)
         {
-            return await CreateInvoiceClient().RequestInvoiceWebhookToBeResent(invoiceId).ConfigureAwait(false);
+            return await CreateInvoiceClient().RequestInvoiceWebhookToBeResent(invoiceId, invoiceToken).ConfigureAwait(false);
         }
         
         /// <summary>
@@ -420,12 +424,16 @@ public async Task<Refund> UpdateRefundByGuid(string refundGuid, string status)
         ///     Send a refund notification
         /// </summary>
         /// <param name="refundId">A BitPay refundId </param>
+        /// <param name="refundToken">
+        ///    The resource token for the refundId. 
+        ///    This token can be retrieved from the Bitpay's refund object.
+        /// </param>
         /// <returns>An updated Refund Object </returns>
         /// <throws>RefundCreationException RefundCreationException class </throws>
         /// <throws>BitPayException BitPayException class </throws>
-        public async Task<Boolean> SendRefundNotification(string refundId)
+        public async Task<Boolean> SendRefundNotification(string refundId, string refundToken)
         {
-            return await CreateRefundClient().SendRefundNotification(refundId).ConfigureAwait(false);
+            return await CreateRefundClient().SendRefundNotification(refundId, refundToken).ConfigureAwait(false);
         }
 
         /// <summary>
diff --git a/BitPay/Clients/InvoiceClient.cs b/BitPay/Clients/InvoiceClient.cs
index 1c7bf95..59d9cf4 100644
--- a/BitPay/Clients/InvoiceClient.cs
+++ b/BitPay/Clients/InvoiceClient.cs
@@ -310,13 +310,17 @@ public async Task<Invoice> CancelInvoiceByGuid(string guidId, bool forceCancel =
         ///     Request a webhook to be resent.
         /// </summary>
         /// <param name="invoiceId">Invoice ID.</param>
+        /// <param name="invoiceToken">
+        ///    The resource token for the invoiceId. 
+        ///    This token can be retrieved from the Bitpay's invoice object.
+        /// </param>
         /// <returns>Status of request</returns>
         /// <exception cref="BitPayGenericException">BitPayGenericException class</exception>
         /// <exception cref="BitPayApiException">BitPayApiException class</exception>
-        public async Task<bool> RequestInvoiceWebhookToBeResent(string invoiceId)
+        public async Task<bool> RequestInvoiceWebhookToBeResent(string invoiceId, string invoiceToken)
         {
             var parameters = ResourceClientUtil.InitParams();
-            parameters.Add("token", _accessTokens.GetAccessToken((Facade.Merchant)));
+            parameters.Add("token", invoiceToken);
 
             string json = null!;
             
@@ -407,4 +411,4 @@ public async Task<Invoice> PayInvoice(string invoiceId, string status)
             return invoice;
         }
     }
-}
\ No newline at end of file
+}
diff --git a/BitPay/Clients/RefundClient.cs b/BitPay/Clients/RefundClient.cs
index a6abbed..8ffcb09 100644
--- a/BitPay/Clients/RefundClient.cs
+++ b/BitPay/Clients/RefundClient.cs
@@ -302,13 +302,17 @@ public async Task<Refund> CancelByGuid(string refundGuid)
         ///     Send a refund notification
         /// </summary>
         /// <param name="refundId">A BitPay refundId </param>
+        /// <param name="refundToken">
+        ///    The resource token for the refundId. 
+        ///    This token can be retrieved from the Bitpay's refund object.
+        /// </param>
         /// <returns>An updated Refund Object </returns>
         /// <exception cref="BitPayGenericException">BitPayGenericException class</exception>
         /// <exception cref="BitPayApiException">BitPayApiException class</exception>
-        public async Task<bool> SendRefundNotification(string refundId)
+        public async Task<bool> SendRefundNotification(string refundId, string refundToken)
         {
             var parameters = ResourceClientUtil.InitParams();
-            parameters.Add("token", _accessTokens.GetAccessToken(Facade.Merchant));
+            parameters.Add("token", refundToken);
             
             string json;
             
@@ -342,4 +346,4 @@ public async Task<bool> SendRefundNotification(string refundId)
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/BitPay/Exceptions/BitPayApiException.cs b/BitPay/Exceptions/BitPayApiException.cs
index 67233ea..0b09626 100644
--- a/BitPay/Exceptions/BitPayApiException.cs
+++ b/BitPay/Exceptions/BitPayApiException.cs
@@ -30,5 +30,9 @@ public string? Code
                 return _code;
             }
         }
+
+        protected BitPayApiException(SerializationInfo info, StreamingContext context) : base(info, context)
+        {
+        }
     }
-}
\ No newline at end of file
+}
diff --git a/BitPay/Exceptions/BitPayException.cs b/BitPay/Exceptions/BitPayException.cs
index a05c55f..5ef4976 100644
--- a/BitPay/Exceptions/BitPayException.cs
+++ b/BitPay/Exceptions/BitPayException.cs
@@ -15,5 +15,9 @@ public class BitPayException : Exception
         public BitPayException(string message) : base(message)
         {
         }
+
+        protected BitPayException(SerializationInfo info, StreamingContext context) : base(info, context)
+        {
+        }
     }
-}
\ No newline at end of file
+}
diff --git a/BitPay/Exceptions/BitPayGenericException.cs b/BitPay/Exceptions/BitPayGenericException.cs
index f5e65c6..2a048af 100644
--- a/BitPay/Exceptions/BitPayGenericException.cs
+++ b/BitPay/Exceptions/BitPayGenericException.cs
@@ -15,5 +15,9 @@ public class BitPayGenericException : BitPayException
         public BitPayGenericException(string message) : base(message)
         {
         }
+
+        protected BitPayGenericException(SerializationInfo info, StreamingContext context) : base(info, context)
+        {
+        }
     }
-}
\ No newline at end of file
+}
diff --git a/BitPay/Exceptions/BitPayValidationException.cs b/BitPay/Exceptions/BitPayValidationException.cs
index 7c3913e..34cfd7f 100644
--- a/BitPay/Exceptions/BitPayValidationException.cs
+++ b/BitPay/Exceptions/BitPayValidationException.cs
@@ -15,5 +15,9 @@ public class BitPayValidationException : BitPayGenericException
         public BitPayValidationException(string message) : base(message)
         {
         }
+
+        protected BitPayValidationException(SerializationInfo info, StreamingContext context) : base(info, context)
+        {
+        }
     }
-}
\ No newline at end of file
+}
diff --git a/BitPay/Models/Invoice/RecipientStatus.cs b/BitPay/Models/Invoice/RecipientStatus.cs
index 534b57c..2a0c6c3 100644
--- a/BitPay/Models/Invoice/RecipientStatus.cs
+++ b/BitPay/Models/Invoice/RecipientStatus.cs
@@ -3,7 +3,7 @@
 
 namespace BitPay.Models.Invoice
 {
-    public class RecipientStatus
+    public static class RecipientStatus
     {
         public const string Active = "active";
         public const string Invited = "invited";
@@ -12,4 +12,4 @@ public class RecipientStatus
         public const string Unverified = "unverified";
         public const string Verified = "verified";
     }
-}
\ No newline at end of file
+}
diff --git a/BitPay/Models/Invoice/Refund.cs b/BitPay/Models/Invoice/Refund.cs
index 3ef396d..e81d444 100644
--- a/BitPay/Models/Invoice/Refund.cs
+++ b/BitPay/Models/Invoice/Refund.cs
@@ -27,6 +27,9 @@ public class Refund
         [JsonProperty(PropertyName = "guid")]
         public string? ResourceGuid { get; set; }
 
+        [JsonProperty(PropertyName = "token")] 
+        public string? Token { get; set; }
+
         [JsonProperty(PropertyName = "refundAddress")]
         public string? RefundAddress { get; set; }
 
diff --git a/BitPayFunctionalTest/BitPayFunctionalTest.cs b/BitPayFunctionalTest/BitPayFunctionalTest.cs
index d79cb06..cabf93c 100644
--- a/BitPayFunctionalTest/BitPayFunctionalTest.cs
+++ b/BitPayFunctionalTest/BitPayFunctionalTest.cs
@@ -146,6 +146,7 @@ public async Task it_should_test_refunds_requests()
             var refundToCreateRequest = new Refund(invoiceId: invoiceId, amount: 10.0M);
             var refund = await _client.CreateRefund(refundToCreateRequest);
             var refundId = refund.Id!;
+            var refundToken = refund.Token!;
 
             var retrieveRefund = await _client.GetRefund(refundId);
             Assert.Equal(refundId, retrieveRefund.Id);
@@ -158,7 +159,7 @@ public async Task it_should_test_refunds_requests()
             Assert.NotEmpty(retrieveRefundByInvoiceId);
             retrieveRefundByInvoiceId.Exists(refundByInvoice => refundByInvoice.Invoice == invoiceId);
 
-            var refundNotification = await _client.SendRefundNotification(refundId);
+            var refundNotification = await _client.SendRefundNotification(refundId, refundToken);
             Assert.True(refundNotification);
 
             var cancelRefund = await _client.CancelRefund(refundId);
@@ -480,4 +481,4 @@ private static string GetBitPayUnitTestPath()
             return bitPayUnitTestPath;
         }
     }
-}
\ No newline at end of file
+}
diff --git a/BitPayUnitTest/ClientTest.cs b/BitPayUnitTest/ClientTest.cs
index 82bac98..27c56e6 100644
--- a/BitPayUnitTest/ClientTest.cs
+++ b/BitPayUnitTest/ClientTest.cs
@@ -7,6 +7,7 @@
 using BitPay;
 using BitPay.Clients;
 using BitPay.Exceptions;
+using BitPay.Models;
 using BitPay.Models.Bill;
 using BitPay.Models.Invoice;
 using BitPay.Models.Payout;
@@ -14,6 +15,8 @@
 
 using Moq;
 
+using Newtonsoft.Json;
+
 using Environment = BitPay.Environment;
 using SystemEnvironment = System.Environment;
 
@@ -826,11 +829,15 @@ public void it_should_cancel_invoice_by_guid()
         [Fact]
         public void it_should_request_invoice_webhook_to_be_resent()
         {
+            var invoiceToken = "cM78LHk17Q8fktDE6QLBBFfvH1QKBhRkHibTLcxhgzsu3VDRvSyu3CGi17DuwYxhT";var responseObject = new 
+            {
+                token = invoiceToken
+            };
             // given
             HttpContent response = new StringContent(File.ReadAllText(GetJsonResponsePath() + "invoiceWebhookResponse.json"));
             _bitPayClient.Setup(b => b.Post(
                 "invoices/Hpqc63wvE1ZjzeeH4kEycF/notifications",
-            "{\"token\":\"merchantToken\"}",
+                JsonConvert.SerializeObject(responseObject),
                 false
             )).ReturnsAsync(new HttpResponseMessage
             {
@@ -841,7 +848,7 @@ public void it_should_request_invoice_webhook_to_be_resent()
             });
 
             // when
-            var result = GetTestedClassAsMerchant().RequestInvoiceWebhookToBeResent("Hpqc63wvE1ZjzeeH4kEycF").Result;
+            var result = GetTestedClassAsMerchant().RequestInvoiceWebhookToBeResent("Hpqc63wvE1ZjzeeH4kEycF", invoiceToken).Result;
             
             // then
             Assert.True(result);
@@ -1665,11 +1672,16 @@ public void it_should_update_refund_by_guid()
         [Fact]
         public void it_should_send_refund_notification()
         {
+            var refundToken = "cM78LHk17Q8fktDE6QLBBFfvH1QKBhRkHibTLcxhgzsu3VDRvSyu3CGi17DuwYxhT";
+            var responseObject = new 
+            {
+                token = refundToken
+            };
             // given
             HttpContent response = new StringContent(File.ReadAllText(GetJsonResponsePath() + "sendRefundNotificationResponse.json"));
             _bitPayClient.Setup(b => b.Post(
                 "refunds/WoE46gSLkJQS48RJEiNw3L/notifications",
-                "{\"token\":\"merchantToken\"}",
+                JsonConvert.SerializeObject(responseObject),
                 true
             )).ReturnsAsync(new HttpResponseMessage
             {
@@ -1679,7 +1691,7 @@ public void it_should_send_refund_notification()
             });
 
             // when
-            var result = GetTestedClassAsMerchant().SendRefundNotification("WoE46gSLkJQS48RJEiNw3L").Result;
+            var result = GetTestedClassAsMerchant().SendRefundNotification("WoE46gSLkJQS48RJEiNw3L", refundToken).Result;
             
             // then
             Assert.True(result);