diff --git a/api/core/model_runtime/model_providers/spark/llm/_client.py b/api/core/model_runtime/model_providers/spark/llm/_client.py
index a4659454eed30..4c8790141d26a 100644
--- a/api/core/model_runtime/model_providers/spark/llm/_client.py
+++ b/api/core/model_runtime/model_providers/spark/llm/_client.py
@@ -148,7 +148,8 @@ def gen_params(self, messages: list, user_id: str,
         data = {
             "header": {
                 "app_id": self.app_id,
-                "uid": user_id
+                # resolve this error message => $.header.uid' length must be less or equal than 32
+                "uid": user_id[:32] if user_id else None
             },
             "parameter": {
                 "chat": {