FreshMVVM Master detail with custom MasterPage

Hello
I use FRESHMVVM in my app.
I created a massterdetail page as well:

var masterPage = FreshPageModelResolver.ResolvePageModel();
var detailPage = FreshPageModelResolver.ResolvePageModel();
var masterDetailNav = new FreshMasterDetailNavigationContainer();
masterDetailNav.Init("Menu");
masterDetailNav.Master = masterPage;
masterDetailNav.Detail = detailPage;
MainPage = masterDetailNav;
}

I would like that when a MenuItem is pressed it is navigated to the new page keeping the menu present.

I am doing this way but the new page is opened without menu.

await CoreMethods.PushPageModel(item.ViewModelType);

Can you help me?
Thank you