Not able to click an button on subgrid

Question

I am using easy repro framework and having difficulty as i am not able to click on a button in the subgrid inside a tab i used multiple code but no luck.i am always facing CS0103 error this is my code:i am having trouble with last line of code:

              var client = new WebClient(TestSettings.Options);     
              using (var xrmApp = new XrmApp(client))

              xrmApp.Entity.SelectTab("Offer");
              xrmApp.ThinkTime(5000);
              xrmBrowser.Entity.ClickSubgridAddButton("New Offer");               

tried changing Xrmbrowser to XrmApp butresult in an error