diff --git a/src/vs/workbench/contrib/chat/common/chatServiceImpl.ts b/src/vs/workbench/contrib/chat/common/chatServiceImpl.ts
index 8812823710419..1b82204af0f2c 100644
--- a/src/vs/workbench/contrib/chat/common/chatServiceImpl.ts
+++ b/src/vs/workbench/contrib/chat/common/chatServiceImpl.ts
@@ -394,7 +394,7 @@ export class ChatService extends Disposable implements IChatService {
 			return model;
 		}
 
-		const sessionData = this._persistedSessions[sessionId];
+		const sessionData = revive<ISerializableChatData>(this._persistedSessions[sessionId]);
 		if (!sessionData) {
 			return undefined;
 		}