403 Forbidden error when uploading files from Postman to PHP API

I am trying to upload files from Postman using PHP API. I’m getting a 403 forbidden error:

<html>

<head>
    <title>403 Forbidden</title>
</head>

<body>
    <center>
        <h1>403 Forbidden</h1>
    </center>
</body>

</html>