diff --git a/apps/readest-app/src/app/reader/components/sidebar/TOCView.tsx b/apps/readest-app/src/app/reader/components/sidebar/TOCView.tsx
index 5eb3d23a..7a0c11f9 100644
--- a/apps/readest-app/src/app/reader/components/sidebar/TOCView.tsx
+++ b/apps/readest-app/src/app/reader/components/sidebar/TOCView.tsx
@@ -85,10 +85,10 @@ const TOCItemView: React.FC<{
       </span>
       {item.subitems && isExpanded && (
         <ol role='group'>
-          {item.subitems.map((subitem) => (
+          {item.subitems.map((subitem, index) => (
             <TOCItemView
               bookKey={bookKey}
-              key={subitem.label}
+              key={`${index}-${subitem.href}`}
               item={subitem}
               depth={depth + 1}
               setCurrentHref={setCurrentHref}
@@ -152,10 +152,10 @@ const TOCView: React.FC<{
       <div className='max-h-[calc(100vh-173px)] overflow-y-auto rounded pt-2'>
         <ul role='tree' ref={tocRef} className='overflow-y-auto px-2'>
           {toc &&
-            toc.map((item) => (
+            toc.map((item, index) => (
               <TOCItemView
                 bookKey={bookKey}
-                key={item.label}
+                key={`${index}-${item.href}`}
                 item={item}
                 depth={0}
                 setCurrentHref={setCurrentHref}
diff --git a/apps/readest-app/src/store/readerStore.ts b/apps/readest-app/src/store/readerStore.ts
index 6eb2af9e..5c3cb473 100644
--- a/apps/readest-app/src/store/readerStore.ts
+++ b/apps/readest-app/src/store/readerStore.ts
@@ -279,8 +279,8 @@ export const useReaderStore = create<ReaderStore>((set, get) => ({
             config: {
               ...book.config,
               lastUpdated: Date.now(),
-              href: tocItem.href,
-              chapter: tocItem.label,
+              href: tocItem?.href,
+              chapter: tocItem?.label,
               progress: [pageinfo.current, pageinfo.total],
               location,
               section,
@@ -290,9 +290,9 @@ export const useReaderStore = create<ReaderStore>((set, get) => ({
               ...book.progress,
               progress: [pageinfo.current, pageinfo.total],
               location,
-              tocHref: tocItem.href,
-              tocLabel: tocItem.label,
-              tocId: tocItem.id,
+              tocHref: tocItem?.href,
+              tocLabel: tocItem?.label,
+              tocId: tocItem?.id,
               section,
               pageinfo,
               range,