Store form value in an array of strings in nodejs - node.js

Question

So I have a post method in my nodejs application and I want to send a form from my ejs file to an array in one of my models. In the ejs file, I have a select option for the user to enter a list of subjects. Once submitted, I cannot get the values from the select option. I tried to store it in an array but it shows undefined. I have an instructor model where it stores the subjects fields in a list of string array. I am not sure what to do. Here is what I have:
admin.js
router.get('/newInstructor', isLoggedIn, function(req, res) {
res.render('newInstructor.ejs');
});
router.post('/newInstructor', isLoggedIn, function(req, res) {
var lisOfSubjects = [req.body.listOfSubjects];
console.log('Subjects -> ' + lisOfSubjects);
var newInstructor = new Instructor ({
firstName: req.body.firstName,
lastName: req.body.lastName,
email: req.body.email,
officeNumber: req.body.officeNum,
cellNumber: req.body.cellNum,
address: {
address1: req.body.address,
address2: req.body.address2,
city: req.body.city,
state: req.body.state,
zipCode: req.body.zip
},
subjects: lisOfSubjects,
officeLocation: req.body.officeLocation
});
console.log(newInstructor);
});
ejs view file
<!-- js function to insert and remove from the select option-->
<script>
function insertTeachingSelect() {
var text = document.getElementById("subject").value;
console.log(text);
var select = document.getElementById("listOfSubjects");
select.options[select.options.length] = new Option(text, 'Value1');
}
function removeTeachingSelect() {
var removeSelect = document.getElementById("listOfSubjects");
removeSelect.remove(removeSelect.selectedIndex);
}
</script>
......
<div class="form-group">
<div class="form-row">
<div class="col-md-4">
<div class="form-label-group">
<input type="text" id="subject" name="subject" class="form-control">
<label for="Enter subject">Enter subject</label>
</div>
</div>
<div class="col-md-2">
<div class="form-label-group">
<input type="button" onclick="insertTeachingSelect()" class="btn btn-primary btn-block" value="Add more">
<input type="button" onclick="removeTeachingSelect()" class="btn btn-primary btn-block" value="Remove">
</div>
</div>
<div class="col-md-6">
<div class="form-label-group">
<input type="text" id="officeLocation" name="officeLocation" class="form-control" placeholder="Office location" required="required">
<label for="officeLocation">Office location</label>
</div>
</div>
</div>
</div>
<div class="form-group">
<div class="form-row">
<div class="col-md-4">
<div class="form-label-group">
<select id="listOfSubjects" name="listOfSubjects"size="5"></select>
</div>
</div>
</div>
</div>
<div class="form-group ">
<div class="form-row">
<div class="col-md-6 mx-auto">
<div class="form-label-group">
<button type="submit" class="btn btn-primary btn-block">Submit</button>