diff --git a/notifier/notifier.go b/notifier/notifier.go
index a375a0749..eb83c45b0 100644
--- a/notifier/notifier.go
+++ b/notifier/notifier.go
@@ -475,10 +475,6 @@ func (n *Manager) sendAll(alerts ...*Alert) bool {
 		numSuccess atomic.Uint64
 	)
 	for _, ams := range amSets {
-		if len(ams.ams) == 0 {
-			continue
-		}
-
 		var (
 			payload  []byte
 			err      error
@@ -487,6 +483,10 @@ func (n *Manager) sendAll(alerts ...*Alert) bool {
 
 		ams.mtx.RLock()
 
+		if len(ams.ams) == 0 {
+			ams.mtx.RUnlock()
+			continue
+		}
 
 		if len(ams.cfg.AlertRelabelConfigs) > 0 {
 			amAlerts = relabelAlerts(ams.cfg.AlertRelabelConfigs, labels.Labels{}, alerts)