Retrieve a BillFacades: pos, merchantOverview Retrieve a bill by bill ID. Parameters ParameterDescriptionbillIdThe ID of the bill to retrieve. Example Java (Merchant Facade)Java (POS Facade)Bill bill = bitpay.getBill("3Zpmji8bRKxWJo2NJbWX5H"); Bill bill = bitpay.getBill("3Zpmji8bRKxWJo2NJbWX5H", Facade.POS, false);