SQL PHP shell_exec禁用错误。不允许启用。解决方法？

Question

我遇到麻烦了。我的Web主机不允许启用shell_exec，并且我的脚本不断提示我未启用shell_exec。

apply.php

<form action='submit.php' method='post'>
        <div id="apply">
        <ul>
        <li><input type='text' name='nickname' placeholder='Name' id='nickname' class='info'/></li>
        <li><input type='text' name='email' placeholder='Email' id='email' class='info'/></li>
        <li><input type='text' name='discordn' placeholder='Discord Username' id='discordn' maxlength="32"/> <input type='text' name='tag' placeholder='Tag' id='tag' maxlength='4' input type="number"/></li>
       <li> <select placeholder='select one' name='position' id='position'></li>
            <option value="select" id="position">Position</option>
            <option value="developer">Developer</option>
            <option value="tester">Tester</option>
        <li></select></li>
        <li><input type='submit' name='submit' id="submit"></li>
        </ul>
        </div>
    </form>

submit.php（格式正确）

https://pastebin.com/3FW8VMr0