PHP delete problem

Hi, I have a problem with deleting an entry from mysql table. whenever I click the delete button it deletes the last entry from my table and not the one that I've chosen.

here is the codes

echo "<font face='Arial' size='1'>";


	$conn=mysql_connect("localhost","root","");
	if(!$conn)
	{
	die('could not connect!' . mysql_error());
	}

	mysql_select_db("people", $conn);

	
	$result=mysql_query("select * from usersinfo");
	
		echo "<table border='1' align='center'>
		<tr>
		<th> </th>
		<th> username</th>
		<th> password </th>
		<th> action </th>

		</tr>";
	while ($row=mysql_fetch_array($result))
		{
		echo "<tr>";
		echo "<td>";
		echo " <input type='checkbox' value='check'> ";
		echo "</td>";
		echo "<td>" . $row['USERNAME'] . "</td>";
		echo "<td>" . $row['LASTNAME'] . "</td>";
		echo "<td>" . $row['FIRSTNAME'] . "</td>";
		echo "<td>" . $row['MI'] . "</td>";
		echo "<td>" . $row['COMPANY'] . "</td>";
		echo "<td>" . $row['POSITION'] . "</td>";
		echo "<td>" . $row['DEPARTMENT'] . "</td>";
		echo "<td>";
		echo "<form method='post' action='ADD.php'>";
		echo "<input type='hidden' name='ACE_id' value=". $row['ID'] .">";
		echo "<input type='submit'>";
		echo "</td>";
		echo "</tr>";
		}
		

		echo "</table>";
	mysql_close($conn);

echo "</td>"; ]

and the delete code

<?php
function del_userinfo( ) {

$DELid=$_POST["ACE_id"];


$con = mysql_connect("localhost","root","");
if (!$con)
  {
  die('Could not connect: ' . mysql_error());
  }

mysql_select_db("people", $con);

mysql_query("DELETE FROM usersinfo WHERE ID='" . $DELid . "'");

mysql_close($con);


}
?>

help anyone .., Thank You in advance />