Image upload not transferring file

Hi newby here could someone please tell me why the move_uploaded_file function isn’t working for me,


$id = mysqli_insert_id($db_conx);
	// Place image in the folder
	$newname = "$id.jpg";
	echo $newname;
	$target ="upload/$newname";
	echo $target;
	if (isset($_POST['uploaded_file'])) {
	move_uploaded_file($_FILES['uploaded_file']['tmp_name'],$target);
	} 

does $target look right when you echo it? Are you sure you named your file field “uploaded_file” on your form?