Advance JSON deserialize > SQL Insert

Hope someone can please help

I want to Insert JSON Values to a SQL Database. It is working, but There is an object within the main object, which I cannot seem to retrieve the value.

Here is my JSON code

{"items":[{"uid":"b003a6ad8ef543dfbebf3ea2d48a1c33","commStatus":"OK","gateway":{"serialNumber":"CA1331305311005","type":null,"uid":"6b8ca67f3eec46c1a94f535c57dd48a3","imei":"353567040903313","macAddress":null},"subscription":{"identifier":"8927000003268372315","state":"INVENTORY","mobileNumber":null,"networkIdentifier":"655103015669848","uid":"1ba23cc6f6bc4a26b42029e4d5b83d1f","ipAddress":"10.13.14.40","operator":"MTN"},"name":"220"},{"uid":"500ed42280594d5b9a3049db15b6e5c9","commStatus":"OK","gateway":{"serialNumber":"CA1301201391004","type":"GX400","uid":"515334dbf5154911aa019520508b8077","imei":"353567041609349","macAddress":"00:14:3E:11:48:0D"},"subscription":{"identifier":"8927000002300070259","state":"INVENTORY","mobileNumber":null,"networkIdentifier":"655103308678726","uid":"073f0fc7ece240e7807db5bc1538d9ef","ipAddress":"10.13.4.51","operator":"MTN"},"name":"4116"}],"count":380,"size":100,"offset":0}

So my first problem I am having, is I have to remove the {"items":, otherwise I don't get any values.

1. So how can I modify the code to include the {"items":

My second problem I am having: gateway is another object, so anything within gateway, I am unable to receive those values. I am trying to get the value of serialNumber, but its returning null.

2. So my 2nd Question is how can I get values within another object