Mikrotik: change usermanager user password using PHP API

I'm trying to create a PHP code that can change a user password using PHP API, here is my code so far:

<?php

require('routeros_api.class.php');

$API = new routerosAPI();

$API->debug = true;

if ($API->connect('192.168.0.101', 'user', 'password')) {

  $API->write('/tool/user-manager/user/getall', false);
    $API->write('=.proplist=username', false);
    $API->write('?username=john');
    $API->write('/tool/user-manager/user/set',false);
    $API->write('password=4321');    

  $READ = $API->read(false);
  $ARRAY = $API->parseResponse($READ);
  print_r($ARRAY);
   $API->disconnect();
}
?>

When I run this code it appears to only return the username I'm searching but the password doesn't change. Any help?

You are using incorrect commands. I was not using PHP API, so some parts will be described by words instead of code.

First of all you need to get ID of the record to edit. If username is john, it will be:

$API->write('/tool/user-manager/user/print', false);
$API->write('=.proplist=.id', false);
$API->write('?username=john');

Read and parse response. For example returned .id is *1. Use this to change password:

$API->write('/tool/user-manager/user/set', false);
$API->write('=.id=*1', false);
$API->write('=password=new_pass');