Windows Help unban system!

[mokerosan]

how to fix this error?

A PHP Error was encountered

Severity: Notice

Message: Undefined index: custom

Filename: pages/unban.php

Line Number: 20

unban.php

Query principal
SELECT `id` FROM `accounts` WHERE `name` = $custom LIMIT 1

Opcion A
DELETE FROM `bans` WHERE `value` = $customid;

Opcion B

DELETE FROM `bans` WHERE `value` = $custom;
UPDATE `accounts` SET `warnings` = warnings -1 WHERE name = $custom;


<?php
require ("config.php");
$ots = POT::getInstance();
$ots->connect(POT::DB_MYSQL, connection());
$SQL = $ots->getDBHandle();

// Definitions
[COLOR="#0000FF"]$custom = stripslashes(ucwords(strtolower(trim($_REQUEST['custom']))));[/COLOR]  <---- line 20

if(isset($_REQUEST['amount']) && isset($custom)) {
	// Query should go here

	if(!$ok) {
		$title = "Error";
		$content = "You do not have enough points!";
	} else {
		$title = "Congratulations, your account was unbanned!";
		$content = "Don't get banned again!";
	}
	echo '
		<div class="message"><div class="title">'.$title.'</div><div class="content">'.$content.'</div></div>
	';
} else {
?>
<div class='message'>
	<div class='title'>Unban Account</div>
	<div class='content'>
		<table border="0" cellspacing="1" cellpadding="5" width="100%" class="cellspadding">
 			<tr class="tableheader">
  				<td><strong>Offer Description</strong></td>
  				<td width="15%" align="center"><strong>Points</strong></td>
 			</tr>
			<tr class="tablerow">
  				<td><b>A:</b> Unban one account</td>
  				<td align="center"><strong>20 Points</strong></td>
 			</tr>
			<tr class="tablerow">
  				<td><b>B:</b> Unban one account and all warnings</td>
  				<td align="center"><strong>28 Points</strong></td>
 			</tr>
		</table>
		<div align="center" style="color:green;">
			<i>*Remember that every time you get banned.. one ban-warning gets added to your account.. after 3 ban-warnings your account will be deleted!</i>
        </div>
        <div align="center">
			<form action="p/v/unban" method="post">
				<br />
				<b>Account number:</b> <input type="text"  name="custom" value="">
				<br />
				<font color="red"><i>*Put your account number here!</i></font><br />
				<b>Package type:</b>
				<select name="amount">
  					<option value="20">Unban A</option>
  					<option value="28">Unban B</option>
				</select>
				<br />
				<input value="Buy package!" type="submit"> 
			</form>
		</div>
	</div>
</div>
<?php
}
?>