output blijft leeg

<?php
//select.php
$output = '';
$connect = mysqli_connect("localhost", "username", "password", "databasename");
if (!$connect){
	echo "niet verbonden met database";
}

if(isset($_POST["action"])){
$procedure = "
	CREATE PROCUDURE selectUser()
	BEGIN 
	SELECT * FROM users ORDER BY id DESC;
	END;
	";
	
	if(mysqli_query($connect, "DROP PROCEDURE IF EXISTS selectUser")){
        //tot hier krijg ik output
		if(mysqli_query($connect, $procedure)){
        //hier krijg ik geen output meer het probleem zit waarschijnlijk in bovenstaande lijn maar zie het niet
			$query = "CALL selectUser()";
			$result = mysqli_query($connect, $query);
			$output .='
				<table>
					<tr>
						<th width="35%">Voornaam</th>
						<th width="35%">Achternaam</th>
						<th width="15%">update</th>
						<th width="15%">Verwijderen</th>
					</tr>
			';
			if(mysqli_num_rows($result) > 0){
				while($row = mysqli_fetch_array($result)){
					$output .='
						<tr>
							<td>'.$row["firstname"].'</td>
							<td>'.$row["lastname"].'</td>
							<td><button type="button" name="update" id="'.$row["id"].'" class="update">Update</button</td>
							<td><button type="button" name="Delete" id="'.$row["id"].'" class="update">Delete</button</td>
						</tr>
					';
				}
			
			}else{
				$output .='
				<tr>
					<td colspan="4">Data not found</td>
				</tr>
				';
			}
			$output .='</table>';
			echo $output;
		}
	
	}
	
}
?>