2.get_Item(TKey key)
at LiteDB.IndexService.AddNode(CollectionIndex index, BsonValue key, Byte level, IndexNode last)
at LiteDB.LiteEngine.InsertDocument(CollectionPage col, BsonDocument doc, BsonType autoId)
at LiteDB.LiteEngine.<>c__DisplayClass33_0.<Upsert>b__0(CollectionPage col)
at LiteDB.LiteEngine.Transaction[T](String collection, Boolean addIfNotExists, Func
2 action)