diff --git a/app/helpers/call_llm.py b/app/helpers/call_llm.py
index 5199b787..44b54890 100644
--- a/app/helpers/call_llm.py
+++ b/app/helpers/call_llm.py
@@ -98,8 +98,8 @@ def _partial_stt_callback(text: str) -> None:
         # Init buffer if empty
         if not stt_buffer:
             stt_buffer.append("")
-        # Append the recognition
-        stt_buffer[-1] += text
+        # Replace the partial recognition
+        stt_buffer[-1] = text
         logger.debug("Partial recognition: %s", stt_buffer)
 
     def _complete_stt_callback(text: str) -> None: