Cannot read checkbox when not ticked

I am trying to check if a checkbox is ticked but when the checkbox is not ticked it wont work and gives the error: "TypeError: Cannot read property 'PrivateCheck' of undefined" and points to the line with this code:

let isprivare = req.body['PrivateCheck'];

This is the check box I am trying to get input from

<form class="fileupload" action="upload" method="post" enctype="multipart/form-data">
<input type="checkbox" id="PrivateCheck" name="PrivateCheck" />
</form>

Thank you.