diff --git a/src/service/Service.ts b/src/service/Service.ts
index 5288706..870720e 100644
--- a/src/service/Service.ts
+++ b/src/service/Service.ts
@@ -141,11 +141,12 @@ export class Service {
     const nodes = nodeStrs.map(data => parseNode(data))
     const nodeMap = nodes.toMap('processId')
     const countObjs = await client.hgetall(ROOM_COUNT_KEY)
-    for (let key of Object.keys(countObjs)) {
-      if (!nodeMap.has(key)) {
-        await client.hdel(ROOM_COUNT_KEY, key)
+    if (countObjs) {
+      for (let key of Object.keys(countObjs)) {
+        if (!nodeMap.has(key)) {
+          await client.hdel(ROOM_COUNT_KEY, key)
+        }
       }
     }
-
   }
 }