diff --git a/src/Bundle/ChillMainBundle/Export/ExportDataNormalizerTrait.php b/src/Bundle/ChillMainBundle/Export/ExportDataNormalizerTrait.php
index 9dafd597b..44cdc8310 100644
--- a/src/Bundle/ChillMainBundle/Export/ExportDataNormalizerTrait.php
+++ b/src/Bundle/ChillMainBundle/Export/ExportDataNormalizerTrait.php
@@ -11,6 +11,7 @@ declare(strict_types=1);
 
 namespace Chill\MainBundle\Export;
 
+use Doctrine\Common\Collections\Collection;
 use Doctrine\Persistence\ObjectRepository;
 
 trait ExportDataNormalizerTrait
@@ -21,10 +22,13 @@ trait ExportDataNormalizerTrait
     public function normalizeDoctrineEntity(object|array $entity): array|int
     {
         if (is_array($entity)) {
-            return array_values(array_map(static fn (object $entity) => $entity->getId(), $entity));
+            return array_values(array_filter(array_map(static fn (object $entity) => $entity->getId(), $entity), fn ($value) => null !== $value));
+        }
+        if ($entity instanceof Collection) {
+            return $this->normalizeDoctrineEntity($entity->toArray());
         }
 
-        return $entity->getId();
+        return $entity?->getId();
     }
 
     public function denormalizeDoctrineEntity(array|int $id, ObjectRepository $repository): object|array