elimina chat utente loggato

[imperor]

elimina chat utente loggato

buongiorno sto tentando di eliminare due tabelle ho provato cosi ma non va :

CREATE TABLE `chats` (
  `chat_id` int(11) NOT NULL,
  `from_id` int(11) NOT NULL,
  `to_id` int(11) NOT NULL,
  `message` text NOT NULL,
  `opened` tinyint(1) NOT NULL DEFAULT 0,
  `created_at` datetime NOT NULL DEFAULT current_timestamp()
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- --------------------------------------------------------

--
-- Table structure for table `conversations`
--

CREATE TABLE `conversations` (
  `conversation_id` int(11) NOT NULL,
  `user_1` int(11) NOT NULL,
  `user_2` int(11) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
-----------------------------------------------------------
<?php  

session_start();

# check if the user is logged in
if(isset($_POST['del'])){
	
	# database connection file
	include 'app/db.conn.php';

	# get the logged in user's username from SESSION
	$user_id = $_SESSION['user_id'];
	$chat_id = $_POST['chat_id'];
	$conversation_id = $_POST['conversation_id'];

$sql = "DELETE chats,conversations
  FROM chat_id AS chats
  LEFT JOIN conversation_id AS conversations ON chat_id.from_id = conversation_id.conversation_id
  WHERE chat_id.from_id = 2;'");
$stmt= $conn->prepare($sql);
$stmt->execute([$chat_id, $conversation_id]);


	header("Location: home.php");
	exit;
}

?>
<form action="delchat.php" method="post" enctype="multipart/form-data">
<input type="hidden" value="<?=$user['username']?>">  
<input type="submit" name="del" value="Elimina chat">
</form>