diff --git a/js/app.js b/js/app.js
index bea1541..9ccf1c6 100644
--- a/js/app.js
+++ b/js/app.js
@@ -576,7 +576,7 @@ const TimeTrack = {
             let vue = this;
 
             this.tickets.forEach((ticket) => {
-                if (ticket.isTimeBox && vue.timeBoxTimeLeft(ticket) <= 0) {
+                if (ticket.isTimeBox && !ticket.notificated && vue.timeBoxTimeLeft(ticket) <= 0) {
                     vue.stopTracking(ticket);
                     // alert('Zeit für "'+ticket.number+'" ist abgelaufen!');
                     if (Notification.permission === 'granted') {
@@ -590,6 +590,8 @@ const TimeTrack = {
                             color: 'red'
                         });
                     }
+
+                    ticket.notificated = true;
                 }
             });
         },