I want to store some data from my input form.

<?php 
include_once"function.php";
if ($_SERVER['REQUEST_METHOD'] == 'POST') {
    $name = $_POST['name'];
    $email = $_POST['email'];
    $items = $_POST['items'];
    $tecnology = $_POST['tecnology'];
    $range = $_POST['price-range'];
    if (empty($name) || empty($email) || empty($items) || empty($tecnology) || empty($range)) {
        echo "Please fill all the fields";
    } else {
        $data = sprintf("%s %s %s %s %s", $name, $email, $items, $tecnology, $range);
         put($data);
        echo $data;
    }
}
?>

function.php file code is 
<?php
function put($data){

    $filename = "E:/xampp/htdocs/cookies/database.text";
    if (is_readable($filename) && is_writable($filename)){
        $fp = fopen($filename, 'a');
        file_put_contents($filename, serialize($data));
        fclose($fp);
    }else {
        echo "Error" . "<br/>";
    }
  
}

This code doesn’t store data in my txt file. But this $data variable stored the whole input.