为什么不能获得paypal帐户余额，但可用余额？

Question

            GetBalanceReq req = new GetBalanceReq();  
            GetBalanceRequestType reqType = new GetBalanceRequestType();
            /*
             * (Optional) Indicates whether to return all currencies. It is
             * one of the following values: 0 Return only the balance for
             * the primary currency holding. 1 Return the balance for each
             * currency holding.
             */
            // 0Return only the balance for the primary currency holding
            // 1Return the balance for each currency holding 
            // Return the balance is valiable balance not total balance 
            reqType.setReturnAllCurrencies("1");
            req.setGetBalanceRequest(reqType);
            GetBalanceResponseType resp = service.getBalance(req);

getbalance只能获得paypal商家账户余额，我希望得到paypal商家账户余额。 我该怎么办才能将总余额转到paypal商户帐户？