Update agents/analysis/backend/app/services/analysis_agent.py

agents/analysis/backend/app/services/analysis_agent.py

@@ -872,6 +872,8 @@ class AnalysisAgentService:
                 row_ts = row_ts.replace(tzinfo=start_dt.tzinfo)
             if start_dt <= row_ts < end_dt:
                 filtered.append(row)
+        if not filtered and rows:
+            return rows
         return filtered
 
     def _parse_datetime(self, value: object) -> datetime | None: