diff --git a/static/js/game.js b/static/js/game.js
index c21eef2..85ba215 100644
--- a/static/js/game.js
+++ b/static/js/game.js
@@ -15,7 +15,7 @@ var modal = document.getElementById('id01');
    var Interval ;
    var time = seconds + tens;
 
-   buttonStart.onclick = () => {
+   function onclckfn() {
       clearInterval(Interval);
       Interval = setInterval(startTimer, 10);
    }
diff --git a/templates/session.html b/templates/session.html
index be9c21a..3cbd610 100644
--- a/templates/session.html
+++ b/templates/session.html
@@ -35,7 +35,7 @@
 		 <div class="wrapper">
 		    <center>
 		       <p><span id="seconds">00</span>:<span id="tens">00</span></p>
-		       <button id="button-start">Start</button>
+		       <button id="button-start" onclick="onclckfn()">Start</button>
 		       <button id="button-stop">Stop</button>
 		       <button id="button-reset">Reset</button>
 		       <form class="modal-content animate" action="http://127.0.0.1:5000/stopuhr" method="POST">