diff --git a/services/ans/include/advanced_notification_service.h b/services/ans/include/advanced_notification_service.h
index 7ed7f0e9918e9660cd015371868c8b959bd20c99..1873e8f3c6ac516ef9b14b7cffdb926f5bae93f5 100644
--- a/services/ans/include/advanced_notification_service.h
+++ b/services/ans/include/advanced_notification_service.h
@@ -1447,7 +1447,7 @@ private:
     std::shared_ptr<PermissionFilter> permissonFilter_ = nullptr;
     std::shared_ptr<NotificationSlotFilter> notificationSlotFilter_ = nullptr;
     std::shared_ptr<NotificationDialogManager> dialogManager_ = nullptr;
-    std::list<std::pair<std::chrono::steady_clock::time_point, std::string>> uniqueKeyList_;
+    std::list<std::pair<std::chrono::system_clock::time_point, std::string>> uniqueKeyList_;
     std::list<std::pair<std::shared_ptr<NotificationRecord>, uint64_t>> delayNotificationList_;
     std::mutex delayNotificationMutext_;
     static std::mutex doNotDisturbMutex_;
diff --git a/services/ans/src/advanced_notification_publish_service.cpp b/services/ans/src/advanced_notification_publish_service.cpp
index 957671badbe82972cb7cf03fc5b2048165d14d8e..fdebca3f9069b6cd0c433d06a73960fe602af4ba 100644
--- a/services/ans/src/advanced_notification_publish_service.cpp
+++ b/services/ans/src/advanced_notification_publish_service.cpp
@@ -2529,7 +2529,7 @@ ErrCode AdvancedNotificationService::DuplicateMsgControl(const sptr<Notification
         return ERR_ANS_DUPLICATE_MSG;
     }
 
-    uniqueKeyList_.emplace_back(std::make_pair(std::chrono::steady_clock::now(), uniqueKey));
+    uniqueKeyList_.emplace_back(std::make_pair(std::chrono::system_clock::now(), uniqueKey));
     return ERR_OK;
 }
 
@@ -2555,10 +2555,10 @@ void AdvancedNotificationService::DeleteDuplicateMsgs(const sptr<NotificationBun
 
 void AdvancedNotificationService::RemoveExpiredUniqueKey()
 {
-    std::chrono::steady_clock::time_point now = std::chrono::steady_clock::now();
+    std::chrono::system_clock::time_point now = std::chrono::system_clock::now();
     auto iter = uniqueKeyList_.begin();
     while (iter != uniqueKeyList_.end()) {
-        if (std::chrono::duration_cast<std::chrono::seconds>(now - (*iter).first).count() > SECONDS_IN_ONE_DAY) {
+        if (std::chrono::duration_cast<std::chrono::seconds>(abs(now - (*iter).first)).count() > SECONDS_IN_ONE_DAY) {
             iter = uniqueKeyList_.erase(iter);
         } else {
             break;
diff --git a/services/ans/test/unittest/advanced_notification_publish_service_test.cpp b/services/ans/test/unittest/advanced_notification_publish_service_test.cpp
index 6512c10ee8252d3c5d0e1e77b1fd3f73459ea971..6d8b0aac1796ceb3862c6ab5b5a3666cb67fe93c 100644
--- a/services/ans/test/unittest/advanced_notification_publish_service_test.cpp
+++ b/services/ans/test/unittest/advanced_notification_publish_service_test.cpp
@@ -862,7 +862,7 @@ HWTEST_F(AnsPublishServiceTest, DuplicateMsgControl_00002, Function | SmallTest
     request->SetAppMessageId("test1");
     auto uniqueKey = request->GenerateUniqueKey();
     advancedNotificationService_->uniqueKeyList_.emplace_back(
-        std::make_pair(std::chrono::steady_clock::now(), uniqueKey));
+        std::make_pair(std::chrono::system_clock::now(), uniqueKey));
 
     auto ret = advancedNotificationService_->DuplicateMsgControl(request);
     ASSERT_EQ(ret, (int)ERR_ANS_DUPLICATE_MSG);
@@ -915,7 +915,7 @@ HWTEST_F(AnsPublishServiceTest, IsDuplicateMsg_00002, Function | SmallTest | Lev
     request->SetAppMessageId("test2");
     auto uniqueKey = request->GenerateUniqueKey();
     advancedNotificationService_->uniqueKeyList_.emplace_back(
-        std::make_pair(std::chrono::steady_clock::now(), uniqueKey));
+        std::make_pair(std::chrono::system_clock::now(), uniqueKey));
 
     auto ret = advancedNotificationService_->IsDuplicateMsg(uniqueKey);
     ASSERT_EQ(ret, true);
@@ -934,7 +934,7 @@ HWTEST_F(AnsPublishServiceTest, RemoveExpiredUniqueKey_00001, Function | SmallTe
     request->SetAppMessageId("test2");
     auto uniqueKey = request->GenerateUniqueKey();
     advancedNotificationService_->uniqueKeyList_.emplace_back(
-        std::make_pair(std::chrono::steady_clock::now() - std::chrono::hours(24), uniqueKey));
+        std::make_pair(std::chrono::system_clock::now() - std::chrono::hours(24), uniqueKey));
 
     sleep(1);
     ASSERT_EQ(advancedNotificationService_->uniqueKeyList_.size(), 1);