add course

<?php

    if(isset($_POST['add_course'])) {

$course_title = trim($_POST['course_title']);
$course_cord = trim($_POST['course_cord']);
$course_hours = trim($_POST['course_hours']);
$course_price = trim($_POST['course_price']);

if(!empty(trim($_POST['course_title'])) && !empty(trim($_POST['course_cord'])) && !empty(trim($_POST['course_hours'])) && !empty(trim($_POST['course_price']))) {

$stmt1 = mysqli_prepare($connection,"INSERT INTO courses(course_title,course_cord,course_hours,course_price)VALUES(?,?,?,?)" );
$stmt1->bind_param("ssss",$course_title,$course_cord,$course_hours,$course_price);
$stmt1->execute();
if(!$stmt1) {
die('Failed'.mysqli_error($stmt1));

}
}
if (empty(trim($_POST['add_course'])) && empty(trim($_POST['course_cord'])) && empty(trim($_POST['course_hours'])) && empty(trim($_POST['course_price']))) {
    header('Location: courses.php?error=' . urlencode(base64_encode("you cant leave it empty")));
}

}



 ?>