diff --git a/app/Export/CSV/BaseExport.php b/app/Export/CSV/BaseExport.php
index 605abff1e2..a3bac0bb12 100644
--- a/app/Export/CSV/BaseExport.php
+++ b/app/Export/CSV/BaseExport.php
@@ -1258,7 +1258,7 @@ class BaseExport
 
         $date_range = $this->input['date_range'];
 
-        if (array_key_exists('date_key', $this->input) && strlen($this->input['date_key']) > 1 && ($table_name && $this->columnExists($table_name, $this->input['date_key']))) {
+        if (array_key_exists('date_key', $this->input) && strlen($this->input['date_key'] ?? '') > 1 && ($table_name && $this->columnExists($table_name, $this->input['date_key']))) {
             $this->date_key = $this->input['date_key'];
         }
 
@@ -1270,6 +1270,9 @@ class BaseExport
             $custom_end_date = now();
         }
 
+        nlog($custom_start_date->format('Y-m-d'));
+        nlog($custom_end_date->format('Y-m-d'));
+        
         switch ($date_range) {
             case 'all':
                 $this->start_date = 'All available data';
diff --git a/app/Export/CSV/TaskExport.php b/app/Export/CSV/TaskExport.php
index bc357d61a9..155d61a88f 100644
--- a/app/Export/CSV/TaskExport.php
+++ b/app/Export/CSV/TaskExport.php
@@ -29,7 +29,7 @@ class TaskExport extends BaseExport
 {
     private $entity_transformer;
 
-    public string $date_key = 'created_at';
+    public string $date_key = 'calculated_start_date';
 
     private string $date_format = 'Y-m-d';