diff --git a/app/common/lists/BaseDataLists.php b/app/common/lists/BaseDataLists.php
index 17cf9ad..3a37109 100644
--- a/app/common/lists/BaseDataLists.php
+++ b/app/common/lists/BaseDataLists.php
@@ -99,10 +99,13 @@ abstract class BaseDataLists implements ListsInterface
             return [];
         }
         $startTime = $this->request->get('start_time');
-        $this->startTime = strtotime($startTime);
+        if($startTime){
+            $this->startTime = strtotime($startTime);
+        }
         $endTime = $this->request->get('end_time');
-        $this->endTime = strtotime($endTime);
-
+        if($endTime){
+            $this->endTime = $startTime??strtotime($endTime);
+        }
         $this->start = $this->request->get('start');
         $this->end = $this->request->get('end');