diff --git a/litellm/integrations/langfuse.py b/litellm/integrations/langfuse.py
index 046a6bcb2f..60c32e212b 100644
--- a/litellm/integrations/langfuse.py
+++ b/litellm/integrations/langfuse.py
@@ -279,7 +279,7 @@ class LangFuseLogger:
                 trace_name = f"litellm-{kwargs.get('call_type', 'completion')}"
 
             if existing_trace_id is not None:
-                trace_params = {"trace_id": existing_trace_id}
+                trace_params = {"id": existing_trace_id}
             else:  # don't overwrite an existing trace
                 trace_params = {
                     "name": trace_name,
@@ -289,10 +289,10 @@ class LangFuseLogger:
                     "session_id": metadata.get("session_id", None),
                 }
 
-            if level == "ERROR":
-                trace_params["status_message"] = output
-            else:
-                trace_params["output"] = output
+                if level == "ERROR":
+                    trace_params["status_message"] = output
+                else:
+                    trace_params["output"] = output
 
             cost = kwargs.get("response_cost", None)
             print_verbose(f"trace: {cost}")
@@ -350,7 +350,8 @@ class LangFuseLogger:
                         kwargs["cache_hit"] = False
                     tags.append(f"cache_hit:{kwargs['cache_hit']}")
                     clean_metadata["cache_hit"] = kwargs["cache_hit"]
-                trace_params.update({"tags": tags})
+                if existing_trace_id is None:
+                    trace_params.update({"tags": tags})
 
             proxy_server_request = litellm_params.get("proxy_server_request", None)
             if proxy_server_request:
@@ -372,6 +373,7 @@ class LangFuseLogger:
 
             print_verbose(f"trace_params: {trace_params}")
 
+            print(f"trace_params: {trace_params}")
             trace = self.Langfuse.trace(**trace_params)
 
             generation_id = None
diff --git a/litellm/tests/test_alangfuse.py b/litellm/tests/test_alangfuse.py
index f0fcf2575e..29718d4746 100644
--- a/litellm/tests/test_alangfuse.py
+++ b/litellm/tests/test_alangfuse.py
@@ -470,8 +470,26 @@ def test_langfuse_existing_trace_id():
 
     new_metadata = {"existing_trace_id": trace_id}
     new_messages = [{"role": "user", "content": "What do you know?"}]
+    new_response_obj = litellm.ModelResponse(
+        id="chatcmpl-9K5HUAbVRqFrMZKXL0WoC295xhguY",
+        choices=[
+            litellm.Choices(
+                finish_reason="stop",
+                index=0,
+                message=litellm.Message(
+                    content="What do I know?",
+                    role="assistant",
+                ),
+            )
+        ],
+        created=1714573888,
+        model="gpt-3.5-turbo-0125",
+        object="chat.completion",
+        system_fingerprint="fp_3b956da36b",
+        usage=litellm.Usage(completion_tokens=37, prompt_tokens=14, total_tokens=51),
+    )
     langfuse_args = {
-        "response_obj": response_obj,
+        "response_obj": new_response_obj,
         "kwargs": {
             "model": "gpt-3.5-turbo",
             "litellm_params": {
@@ -529,6 +547,10 @@ def test_langfuse_existing_trace_id():
 
     langfuse_response_object = langfuse_Logger.log_event(**langfuse_args)
 
+    new_trace_id = langfuse_response_object["trace_id"]
+
+    assert new_trace_id == trace_id
+
     langfuse_client.flush()
 
     time.sleep(2)