fix exchange error

@@ -33,7 +33,10 @@ const exchange = {
         }
 
         exchangeModel.getOrderData(uid, orderCode).then(result => {
-            result.data.address = camelCase(result.data.address);
+            if (result && result.data) {
+                result.data.address = camelCase(result.data.address);
+            }
+
             res.json(result);
         }).catch(next);
     },