$KIRONOS_LOGIN_API = file_get_contents("https://kironweb123.000webhostapp.com/servers/kironos/login.php");
echo $KIRONOS_LOGIN_API;

Uncaught Error: Call to undefined function UserFound() in /storage/ssd3/001/3278001/public_html/projects/KironOS-2/login.php:37 Stack trace: #0 {main} thrown in /storage/ssd3/001/3278001/public_html/projects/KironOS-2/login.php on line 37

$USERNAME = $_GET["uname"];
$USERNAME = strtolower($USERNAME);
$USERNAME = ucfirst($USERNAME);
$PASSWORD = $_GET["pword"];

$KIRONOS_LOGIN_API = file_get_contents("https://kironweb123.000webhostapp.com/servers/kironos/login.php");
echo $KIRONOS_LOGIN_API;

if (UserFound($USERNAME)) {
    if (TryLogin($USERNAME,$PASSWORD)) {
        $_SESSION["kironos_uname"] = $USERNAME;
        ?>
            <script>
                editURL("homepage.php");
            </script>
        <?php
    } else {
        ?>
            <script>
                editURL("index.php");
            </script>
        <?php
   }
} else {
    ?>
        <script>
            editURL("index.php");
        </script>
    <?php
}
        }
?>

<?php

    function UserFound($user) {
        $userdir = "https://kironweb123.000webhostapp.com/projects/KironOS-2/Users/".$user;
    if (file_exists($userdir)) {
        return true;
    } else {
        return false;
    }
}

function TryLogin($user,$pass) {
    $userdir = "https://kironweb123.000webhostapp.com/projects/KironOS-2/Users/".$user;
    $passwFile = $userdir."/passw";
    $corrPassw = file_get_contents($passwFile);
    if ($corrPassw == $pass) {
        return true;
    } else {
        return false;
    }
}

?>