diff --git a/lib/Core/Site/Values/Field.php b/lib/Core/Site/Values/Field.php
index 3de986fe..c4044b1d 100644
--- a/lib/Core/Site/Values/Field.php
+++ b/lib/Core/Site/Values/Field.php
@@ -12,7 +12,7 @@
 
 final class Field extends APIField
 {
-    protected int $id;
+    protected ?int $id;
     protected string $fieldDefIdentifier;
     protected Value $value;
     protected string $languageCode;