private void CreateTicket(int index)//Här anropas event om den valda kund är under 18 år
 {
     if (ListManager.CustomerList[index].Age < 18)
     {
         ErrorMsg += new PrintErrorMsg(GUI.AgeError);
         ErrorMsg?.Invoke();
     }
     else
     {
         VIPTicket newTicket = new VIPTicket();
         newTicket.Buyer = ListManager.CustomerList[index];
         newTicket.Price = InputControllers.PriceController();
         GUI.ShowVIPlevels();
         int choice = InputControllers.VIPChoice();
         newTicket.VIPLevel = (VIPTicket.Level)choice;
         ListManager.TicketList.Add(newTicket);
     }
 }