diff --git a/langfuse/_client/client.py b/langfuse/_client/client.py
index 4c76f11e2..0acdc079b 100644
--- a/langfuse/_client/client.py
+++ b/langfuse/_client/client.py
@@ -3744,7 +3744,7 @@ def update_prompt(
 
         """
         updated_prompt = self.api.prompt_version.update(
-            name=self._url_encode(name),
+            name=self._url_encode(name, is_url_param=True),
             version=version,
             new_labels=new_labels,
         )