diff --git a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/CategoryMutation.kt b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/CategoryMutation.kt
index 311e3224..d852fb46 100644
--- a/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/CategoryMutation.kt
+++ b/server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/CategoryMutation.kt
@@ -16,6 +16,7 @@ import suwayomi.tachidesk.graphql.types.CategoryMetaType
 import suwayomi.tachidesk.graphql.types.CategoryType
 import suwayomi.tachidesk.graphql.types.MangaType
 import suwayomi.tachidesk.manga.impl.Category
+import suwayomi.tachidesk.manga.impl.Category.DEFAULT_CATEGORY_ID
 import suwayomi.tachidesk.manga.impl.util.lang.isEmpty
 import suwayomi.tachidesk.manga.impl.util.lang.isNotEmpty
 import suwayomi.tachidesk.manga.model.dataclass.IncludeInUpdate
@@ -371,7 +372,7 @@ class CategoryMutation {
             if (!patch.addToCategories.isNullOrEmpty()) {
                 val newCategories =
                     buildList {
-                        ids.forEach { mangaId ->
+                        ids.filter { it != DEFAULT_CATEGORY_ID }.forEach { mangaId ->
                             patch.addToCategories.forEach { categoryId ->
                                 val existingMapping =
                                     CategoryMangaTable.select {