update

/ka saya minta tolong koreksi yg salahnya dimna..
Ini proses update gagal terus
//form edit
<main class="main">

<br>
<div class="container-fluid">
<a href="<?php echo base_url('admin/pengumuman'); ?>"><input type="submit" class="btn btn-primary" value="Lihat Informasi"></a>
<hr>
<div class="animated fadeIn">
<div class="row">
<div class="col-sm-6">
<div class="card">
<div class="card-header">
<strong>Menambahkan Info Baru </strong>
<small>Form Edit</small>
</div>
<div class="card-block">
<div class="row">
<div class="col-sm-8">
<!-- Menampilkan Error jika validasi tidak valid -->
<div style="color: red;"><?php echo (isset($message))? $message : ""; ?></div>
<?php
if ($edit) {
# code...
$id = $edit->id;
$info = $edit->info;
$tanggal = $edit->tanggal;
$status = $edit->status;
}else{
$info = "";
$tanggal = "";
$status = "";
}
?>
<form action="<?php echo site_url('admin/update/'.$id) ?>" method="post">
<table cellpadding="8" style="margin:20px auto;">
<tr>
<td class="col-xs-4">Info</td>
<td><input type="text" class="form-control" value="<?php echo $info ?>" name="info"></textarea></td>
</tr>
<tr>
<td>Tanggal</td>
<td><input type="datetime-local" value="<?php echo $tanggal ?>" class="form-control" name="tanggal"></td>
</tr>
<tr>
<td>Status</td>
<td><input type="text" class="form-control" value="<?php echo $status ?>" name="status"></td>
</tr>
<tr>