Store recipients

{
    "version": "latest",
    "apiKey": "abcdefghijklmnopqrstuvwxyz",
    "content": [
        {
            "contentType": "recipientList",
            "tag": "t1",
            "content": "+447777100100,+447777100101,+447777100102",
            "contentEncoding": "utf8",
            "options": {
                "expirationInDays": 0
            }
        }
    ]
}