Bug code html js

Bonjour,

pouvez me dire pourquoi mon code ne marche pas

jai besoin de creer une liste dinamique

en cliquant sur un item doit creer une autre liste

<form action="http://jkorpela.fi/cgi-bin/echo.cgi" id=Schedul> <div >

<div>
<li>
<label dir="ltr" for="Schedul" form="Schedul"> When are you available ? <br></label>

<select name="Schedul" id="Schedul" class="Schedul" onchange="getselectvalue(event)"><option value="_" selected> Choose your moment</option>
<option value="Morning" data-inst="--choose a moment--,9:00,10:00,11:00">Morning</option>
<option value="Afternoon" data-inst="--choose a moment--,13:00,15:00,16:00">Afternoon</option>
<option value="Evening" data-inst="--choose a moment--,19:00,20:00,21:00">Evening</option>
</select>
</div>

<div id="selectplace">

</div>
</li>
<input type=submit form="Schedul"/>
</form>

<script>

function getselectevalue(event) {

let x=event.target[event.target.selectedIndex].getAttribute("data-inst");// Taking the good list in relation with the click
let y=event.target.value;

let newarry=x.split(","); // split the string

let select2 = document.createElement("select");

select2.name="moment";

document.getElementById("selectplace").innerHTML=",";

document.getElementById("selectplace").appendChild(select2);

for (let i = 0; i < newarry.length; i++)

{
let option = document.createElement("option");
option.text=newarry[i];
option.value=y+[event.target.selectedIndex];
select2.appendChild(option);

}
}
</script>