diff --git a/src/PhpSpreadsheet/Writer/Xlsx/Xlfn.php b/src/PhpSpreadsheet/Writer/Xlsx/Xlfn.php
index c322dfc7..c88ef245 100644
--- a/src/PhpSpreadsheet/Writer/Xlsx/Xlfn.php
+++ b/src/PhpSpreadsheet/Writer/Xlsx/Xlfn.php
@@ -140,6 +140,11 @@ class Xlfn
         . '|unique'
         . '|xlookup'
         . '|xmatch'
+        . '|arraytotext'
+        . '|call'
+        . '|let'
+        . '|register[.]id'
+        . '|valuetotext'
         . ')(?=\\s*[(])/i';
 
     /**