diff --git a/src/PhpSpreadsheet/Spreadsheet.php b/src/PhpSpreadsheet/Spreadsheet.php
index fb945399..f45b7e87 100644
--- a/src/PhpSpreadsheet/Spreadsheet.php
+++ b/src/PhpSpreadsheet/Spreadsheet.php
@@ -505,6 +505,7 @@ class Spreadsheet
     {
         $this->disconnectWorksheets();
         $this->calculationEngine = null;
+        $this->cellXfCollection = [];
     }
 
     /**