diff --git a/API/DTOs/KavitaPlus/Metadata/ExternalChapterDto.cs b/API/DTOs/KavitaPlus/Metadata/ExternalChapterDto.cs
index 1dcd8494c..add9ca723 100644
--- a/API/DTOs/KavitaPlus/Metadata/ExternalChapterDto.cs
+++ b/API/DTOs/KavitaPlus/Metadata/ExternalChapterDto.cs
@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using API.DTOs.SeriesDetail;
 
 namespace API.DTOs.KavitaPlus.Metadata;
+#nullable enable
 
 /// <summary>
 /// Information about an individual issue/chapter/book from Kavita+