diff --git a/src/EDI/Parser.php b/src/EDI/Parser.php
index 9166f7a..3a40558 100644
--- a/src/EDI/Parser.php
+++ b/src/EDI/Parser.php
@@ -276,7 +276,10 @@ public function analyseUNH(array $line): void
         }
 
         $this->messageFormat = $lineElement[0];
-        $this->messageDirectory = $lineElement[2];
+
+        if (isset($lineElement[2])) {
+            $this->messageDirectory = $lineElement[2];
+        }
     }
 
     /**