[Kaperstone]

PHP код:

if($run = mysqli_query($con, "SELECT * FROM `users` WHERE `username` = '$username' AND `password` = '$password'")) { 
        if(mysqli_num_rows($run)) {
                while($row = mysqli_fetch_assoc($run)) { 
                        $activation[] = $row['activate']; 
                }
        }else{
                echo "no rows";    
        }
}else{
        echo "query error";
} 


I guess you're trying to get data from multiple rows, then you will need to add [] at the end, so it will use the last free slot.