Using Forms authentication.
When a customer logs in, the CustomerContext.Current is updated immediately (so we get the correct cart by providing CustomerContextFacade.CurrentContactId), but when he logs out, the CustomerContext.Current is not updated immediately so I still get the cart as if he was logged in...
We logout via FormsAuthentication.SignOut();
Episerver Commerce 10.1
By CustomerContext.Current I suppose you meant CustomerContext.Current.CurrentContact?
That depends on the PrincipleInfo.CurrentPrincipal, which itself depends on HttpContext.Current.User, so to make the data refresh, you need to refresh the page after FormsAuthentication.SignOut(). A redirect to the home page is a common practice.
OK - thanks.