Create ASP.NET MVC for Aras

I use code below for ASP.NET MVC. I get property "item_number", but I check in/out to change data in Aras Innovator. I get again in ASP.NET MVC, value not change. Please to help me.

Ex:

1st: item_number = "D-00001" => partNumber = "D-00001"

2nd: item_number = "D-00021"  => partNumber = "D-00001"

Code:

using Aras.IOM;
…
String url = "">myserver/.../InnovatorServer.aspx";
String db = "MyDB";
String user = "admin";
String password = "innovator";
HttpServerConnection conn =
IomFactory.CreateHttpServerConnection( url, db, user, password );
Item login_result = conn.Login();
if( login_result.isError() )
throw new Exception("Login failed");
Innovator inn = IomFactory.CreateInnovator( conn );

Item qryItem = inn.newItem();
qryItem = inn.newItem("Part", "get");
qryItem.setAttribute("select", "item_number, id");
qryItem.setID(myId);

Item results = qryItem.apply();

String partNumber = results.getProperty("item_number");