diff --git a/Classes/Common/IiifManifest.php b/Classes/Common/IiifManifest.php
index c44f985ed..073bf5a53 100644
--- a/Classes/Common/IiifManifest.php
+++ b/Classes/Common/IiifManifest.php
@@ -366,7 +366,7 @@ public function getFileInfo($id): ?array
             $this->fileInfos[$id]['mimeType'] = $this->getFileMimeType($id);
         }
 
-        return $this->fileInfos[$id];
+        return $this->fileInfos[$id] ?? null;
     }
 
     /**
diff --git a/Classes/Common/MetsDocument.php b/Classes/Common/MetsDocument.php
index 8c450a3f3..a26b4e837 100644
--- a/Classes/Common/MetsDocument.php
+++ b/Classes/Common/MetsDocument.php
@@ -221,7 +221,7 @@ public function getFileInfo($id): ?array
             $this->fileInfos[$id]['mimeType'] = $this->getFileMimeType($id);
         }
 
-        return $this->fileInfos[$id];
+        return $this->fileInfos[$id] ?? null;
     }
 
     /**