diff --git a/client/ui/App.tsx b/client/ui/App.tsx
index 1f1ebb0..5130cb8 100644
--- a/client/ui/App.tsx
+++ b/client/ui/App.tsx
@@ -173,7 +173,8 @@ export default function App() {
                 }
                 {
                     isShowChatFragment && <ChatFragment
-                        target={currentChatId} />
+                        target={currentChatId}
+                        key={currentChatId} />
                 }
             </div>
         </div>
diff --git a/client/ui/AppMobile.tsx b/client/ui/AppMobile.tsx
index 8820ccb..f8f0c71 100644
--- a/client/ui/AppMobile.tsx
+++ b/client/ui/AppMobile.tsx
@@ -109,6 +109,7 @@ export default function AppMobile() {
                     <ChatFragment
                         showReturnButton={true}
                         onReturnButtonClicked={() => setIsShowChatFragment(false)}
+                        key={currentChatId}
                         target={currentChatId} />
                 </div>
             </mdui-dialog>
diff --git a/client/ui/useEventListener.ts b/client/ui/useEventListener.ts
index 169f29f..8e92b09 100644
--- a/client/ui/useEventListener.ts
+++ b/client/ui/useEventListener.ts
@@ -3,6 +3,6 @@ import * as React from 'react'
 export default function useEventListener<T extends HTMLElement | null>(ref: React.MutableRefObject<T>, eventName: string, callback: (event: Event) => void) {
     React.useEffect(() => {
         ref.current!.addEventListener(eventName, callback)
-        return () => ref.current!.removeEventListener(eventName, callback)
+        return () => ref.current?.removeEventListener(eventName, callback)
     }, [ref, eventName, callback])
 }