how to delete sub document in sub document on c#

{
  "_id": "binary_stuff",
  "Name": "MyApplication",
  "Settings": [
    {
      "_id": "binary_stuff",
      "Key": "ImportDirectory",
      "Value": "C:\data",
      "Overrides": [{
             "_id": "binary_stuff",
             "Name": "PathDirectory",
             "Value": "C:\anotherData"
       }]
    },
}

   var query = Query.And(Query.EQ("_id", applicationId),
                         Query.EQ("Settings.Key",  "ImportDirectory"));
        var update = Update.Pull("Settings.$.Overrides", new BsonDocument(){
            { "Name", "PathDirectory" }
        });
        database.Applications().Update(query, update);