db.messages.aggregation([{
    "$match": {
        "$and": [{
            "recipient_id": 1607389
        }, {
            "deletedbyrecipient": 0
        }, {
            "blocked": 0
        }]
    }
}, {
    "$sort": {
        "date": -1/*if indexed very slovly worked , if dropIndex no problem*/
    }
}, {
    "$group": {
        "_id": "$sender_id",
        "id": {
            "$first": "$_id"
        },
        "smileid": {
            "$first": "$_id"
        },
        "blocked": {
            "$first": "$blocked"
        },
        "date": {
            "$first": "$date"
        },
        "deletedbyrecipient": {
            "$first": "$deletedbyrecipient"
        },
        "deletedbysender": {
            "$first": "$deletedbysender"
        },
        "seen": {
            "$first": "$seen"
        },
        "recipient_id": {
            "$first": "$recipient_id"
        },
        "sender_id": {
            "$first": "$sender_id"
        },
        "unseencount": {
            "$sum": {
                "$cond": ["$seen", 0, 1]
            }
        }
    }
}, {
    "$sort": {
        "date": -1
    }
}, {
    "$limit": 10
}, {
    "$skip": 0
}]);