table is not Sorted using sorter?

Hi,

I am going to sort table column using Sorter, it is not work correctly.

My code:

var aSorters=[];

  var tabid=this.getView().byId("tabid");

  var sKey=evt.getParameter("sortItem").getKey(); //Postingkey

  var sOrder=evt.getParameter("sortDescending"); // false

  var sorter=new sap.ui.model.Sorter(sKey, sOrder);

  var tItems=tabid.getBinding("items");

  tItems.sort(sorter);

Check below screen: Posting key is not sorted correctly.

Thanks,

Rohit