Xamarin.Andorid can not connect to the Kinvey collection

There is a certain collection on the backend, called "cars". Below is a screen

Here is a description of the entity:

using Newtonsoft.Json; using Kinvey; namespace DaysTaxi.Droid { [JsonObject(MemberSerialization.OptIn)] public class Car : Entity { public Car() { } [JsonProperty("name")] public string Name { get; set; } [JsonProperty("photo_id")] public string PhotoID { get; set; } [JsonProperty("class_id")] public int Class { get; set; } [JsonProperty("_kmd")] public KinveyMetaData Meta { get; set; } [JsonProperty("_acl")] public KinveyMetaData acl { get; set; } [JsonProperty("_id")] public int id { get; set; } } } 

I am trying to connect to this collection from code with the following line, using the API:

  DataStore<Car> cars = DataStore<Car>.Collection("cars", DataStoreType.SYNC); 

An exception is thrown object reference not set to an instance of an object .

At the same time, the rest of the functionality with the backend works: working with users, sessions, files.

As a result: the problem is that I can not connect to the collection from the project code .

I would be happy to help. Thank you in advance!