diff --git a/models/GenericTable.php b/models/GenericTable.php
index c7d2ef23..b076df14 100644
--- a/models/GenericTable.php
+++ b/models/GenericTable.php
@@ -93,10 +93,13 @@ class GenericTable
 			if (empty($column['header']))
 				continue;
 
+			$isSortable = $this->tableIsSortable && !empty($column['is_sortable']);
+			$sortDirection = $key == $this->sort_order && $this->sort_direction === 'up' ? 'down' : 'up';
+
 			$header = [
 				'class' => isset($column['class']) ? $column['class'] : '',
 				'colspan' => !empty($column['header_colspan']) ? $column['header_colspan'] : 1,
-				'href' => !$this->tableIsSortable || empty($column['is_sortable']) ? '' : $this->getLink($this->start, $key, $key == $this->sort_order && $this->sort_direction == 'up' ? 'down' : 'up'),
+				'href' => $isSortable ? $this->getLink($this->start, $key, $sortDirection) : null,
 				'label' => $column['header'],
 				'scope' => 'col',
 				'sort_mode' => $key == $this->sort_order ? $this->sort_direction : null,