diff --git a/internal/querycoordv2/checkers/channel_checker.go b/internal/querycoordv2/checkers/channel_checker.go
index 86bdf3c374..651191e8b5 100644
--- a/internal/querycoordv2/checkers/channel_checker.go
+++ b/internal/querycoordv2/checkers/channel_checker.go
@@ -191,6 +191,10 @@ func (c *ChannelChecker) findRepeatedChannels(ctx context.Context, replicaID int
 	delegatorList := c.dist.ChannelDistManager.GetByCollectionAndFilter(replica.GetCollectionID(), meta.WithReplica2Channel(replica))
 	for _, delegator := range delegatorList {
 		leader := c.dist.ChannelDistManager.GetShardLeader(delegator.GetChannelName(), replica)
+		if leader == nil {
+			log.Warn("channel leader does not exist, skip it", zap.String("channel", delegator.GetChannelName()))
+			continue
+		}
 		// if channel's version is smaller than shard leader's version, it means that the channel is not up to date
 		if delegator.Version < leader.Version && delegator.Node != leader.Node {
 			dupChannels = append(dupChannels, delegator)
diff --git a/internal/querycoordv2/checkers/controller.go b/internal/querycoordv2/checkers/controller.go
index 5df2c5ca0d..cbe2cb2be5 100644
--- a/internal/querycoordv2/checkers/controller.go
+++ b/internal/querycoordv2/checkers/controller.go
@@ -50,6 +50,7 @@ type CheckerController struct {
 	scheduler task.Scheduler
 	checkers  map[utils.CheckerType]Checker
 
+	wg       sync.WaitGroup
 	stopOnce sync.Once
 }
 
@@ -96,7 +97,11 @@ func (controller *CheckerController) Start() {
 	controller.cancel = cancel
 
 	for checker := range controller.checkers {
-		go controller.startChecker(ctx, checker)
+		controller.wg.Add(1)
+		go func() {
+			defer controller.wg.Done()
+			controller.startChecker(ctx, checker)
+		}()
 	}
 }
 
@@ -145,6 +150,8 @@ func (controller *CheckerController) Stop() {
 		if controller.cancel != nil {
 			controller.cancel()
 		}
+
+		controller.wg.Wait()
 	})
 }