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Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Author: yuanqu72

featuremanagement/azuremonitor/_send_telemetry.py

@@ -80,11 +80,16 @@ def track_event(event_name: str, user: str, event_properties: Optional[Dict[str,
         event_properties[TARGETING_ID] = user
 
     # Azure Monitor exporter maps this attribute to customEvent telemetry name.
-    custom_event_attributes = {
-        **event_properties,
-        "microsoft.custom_event.name": event_name,
-    }
-    _event_logger.info(event_name, extra=custom_event_attributes)
+    custom_event_attributes = {**event_properties, "microsoft.custom_event.name": event_name}
+
+    # logging raises KeyError if an `extra` key overwrites a built-in LogRecord attribute (e.g. "name", "message").
+    reserved = logging.makeLogRecord({}).__dict__
+    safe_attributes: Dict[str, Optional[str]] = {}
+    for key, value in custom_event_attributes.items():
+        safe_key = key if key not in reserved else f"telemetry.{key}"
+        safe_attributes[safe_key] = value
+
+    _event_logger.info(event_name, extra=safe_attributes)
 
 
 def publish_telemetry(evaluation_event: EvaluationEvent) -> None: