diff --git a/src/main/java/org/eclipse/uprotocol/client/usubscription/v3/InMemoryUSubscriptionClient.java b/src/main/java/org/eclipse/uprotocol/client/usubscription/v3/InMemoryUSubscriptionClient.java
index 819e757..4fccb98 100644
--- a/src/main/java/org/eclipse/uprotocol/client/usubscription/v3/InMemoryUSubscriptionClient.java
+++ b/src/main/java/org/eclipse/uprotocol/client/usubscription/v3/InMemoryUSubscriptionClient.java
@@ -200,8 +200,9 @@ public CompletionStage<UStatus> unsubscribe(UUri topic, UListener listener, Call
         Objects.requireNonNull(listener, "listener missing");
         Objects.requireNonNull(options, "CallOptions missing");
 
-        final UnsubscribeRequest unsubscribeRequest = UnsubscribeRequest.newBuilder().setTopic(topic).build();
-        
+        final UnsubscribeRequest unsubscribeRequest = UnsubscribeRequest.newBuilder().setTopic(topic)
+                .setSubscriber(SubscriberInfo.newBuilder().setUri(transport.getSource()).build()).build();
+
         return RpcMapper.mapResponseToResult(
             // Send the unsubscribe request
             rpcClient.invokeMethod(UNSUBSCRIBE_METHOD, UPayload.pack(unsubscribeRequest), options),     
diff --git a/src/test/java/org/eclipse/uprotocol/client/usubscription/v3/InMemoryUSubscriptionClientTest.java b/src/test/java/org/eclipse/uprotocol/client/usubscription/v3/InMemoryUSubscriptionClientTest.java
index 14b3033..57499ad 100644
--- a/src/test/java/org/eclipse/uprotocol/client/usubscription/v3/InMemoryUSubscriptionClientTest.java
+++ b/src/test/java/org/eclipse/uprotocol/client/usubscription/v3/InMemoryUSubscriptionClientTest.java
@@ -403,6 +403,8 @@ public void handleSubscriptionChange(UUri topic, SubscriptionStatus status) {
     @Test
     @DisplayName("Test unsubscribe using mock RpcClient and SimplerNotifier")
     void test_unsubscribe_using_mock_RpcClient_and_SimplerNotifier() {
+        when(transport.getSource()).thenReturn(this.source);
+
         when(notifier.registerNotificationListener(any(UUri.class), any(UListener.class)))
             .thenReturn(CompletableFuture.completedFuture(UStatus.newBuilder().setCode(UCode.OK).build()));
 
@@ -434,6 +436,8 @@ void test_unsubscribe_using_mock_RpcClient_and_SimplerNotifier() {
     @Test
     @DisplayName("Test unsubscribe using when invokemethod return an exception")
     void test_unsubscribe_when_invokemethod_return_an_exception() {
+        when(transport.getSource()).thenReturn(this.source);
+
         when(notifier.registerNotificationListener(any(UUri.class), any(UListener.class)))
             .thenReturn(CompletableFuture.completedFuture(UStatus.newBuilder().setCode(UCode.OK).build()));
 
@@ -465,6 +469,8 @@ void test_unsubscribe_when_invokemethod_return_an_exception() {
     @Test
     @DisplayName("Test unsubscribe when invokemethod returned OK but we failed to unregister the listener")
     void test_unsubscribe_when_invokemethod_returned_OK_but_we_failed_to_unregister_the_listener() {
+        when(transport.getSource()).thenReturn(this.source);
+
         when(notifier.registerNotificationListener(any(UUri.class), any(UListener.class)))
             .thenReturn(CompletableFuture.completedFuture(UStatus.newBuilder().setCode(UCode.OK).build()));