Fix DLQ reason/description handling in Service Bus binder

- remove redundant no-arg deadLetter() call so DeadLetterOptions is applied

- strengthen regression test to guard against extra settlement interactions

- update spring changelog for issue #41883

Co-authored-by: sunghyun1999 <32184099@dankook.ac.kr>

Author: rujche

sdk/spring/CHANGELOG.md

@@ -93,6 +93,14 @@ This section includes changes in `spring-cloud-azure-docker-compose` module.
 
 - Upgrade to Jackson 3 to align with Spring Boot 4 ([#49538](https://github.com/Azure/azure-sdk-for-java/issues/49538)).
 
+### Spring Cloud Azure Stream Binder Service Bus
+
+This section includes changes in `spring-cloud-azure-stream-binder-servicebus` module.
+
+#### Bugs Fixed
+
+- Fixed a regression where dead-letter reason and error description were not transmitted because a no-arg `deadLetter()` call settled the message before `deadLetter(options)` was invoked ([#41883](https://github.com/Azure/azure-sdk-for-java/issues/41883)).
+
 ## 6.4.0 (2026-06-01)
 - This release is compatible with Spring Boot 3.5.0-3.5.14. (Note: 3.5.x (x>14) should be supported, but they aren't tested with this release.)
 - This release is compatible with Spring Cloud 2025.0.0-2025.0.2. (Note: 2025.0.x (x>2) should be supported, but they aren't tested with this release.)

sdk/spring/spring-cloud-azure-stream-binder-servicebus/src/main/java/com/azure/spring/cloud/stream/binder/servicebus/implementation/ServiceBusMessageChannelBinder.java

@@ -227,7 +227,6 @@ public <T> void deadLetter(String destination,
             .getHeaders()
             .get(ServiceBusMessageHeaders.RECEIVED_MESSAGE_CONTEXT);
         if (messageContext != null) {
-            messageContext.deadLetter();
             DeadLetterOptions options = new DeadLetterOptions();
             options.setDeadLetterReason(deadLetterReason);
             options.setDeadLetterErrorDescription(deadLetterErrorDescription);

sdk/spring/spring-cloud-azure-stream-binder-servicebus/src/test/java/com/azure/spring/cloud/stream/binder/servicebus/implementation/ServiceBusMessageChannelBinderTest.java

@@ -34,7 +34,9 @@
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
 import static org.mockito.Mockito.when;
 
 class ServiceBusMessageChannelBinderTest {
@@ -104,9 +106,11 @@ void testDeadLetterCalledForError() {
         String description = "testDescription";
         ErrorMessage msg = new ErrorMessage(new RuntimeException(description), originalMessage);
         handler.handleMessage(msg);
+        verify(messageContext, never()).deadLetter();
         verify(messageContext).deadLetter(captor.capture());
         assertEquals("exception-message", captor.getValue().getDeadLetterReason());
         assertEquals(description, captor.getValue().getDeadLetterErrorDescription());
+        verifyNoMoreInteractions(messageContext);
     }
 
     @Test