(Photon) Error: ‘RankedMatchmakingTest’ is missing the class attribute ‘ExtensionOfNativeClass’!

помогите пожалуйста исправить ошибку в unity

‘Axlebolt.Standoff.Matchmaking.RankedMatchmaking.RankedMatchmakingTest’ is missing the class attribute ‘ExtensionOfNativeClass’!

вот сам код using Photon

using UnityEngine.UI;
using UnityEngine;

namespace Axlebolt.Standoff.Matchmaking.RankedMatchmaking
{
    public class RankedMatchmakingTest : PunBehaviour
    {
        [SerializeField]
        private Text _status;
        [SerializeField]
        private Button _searchButton;
        [SerializeField]
        private Button _joinButton;
        [SerializeField]
        private Button _confirmButton;
        [SerializeField]
        private Text _matchmakingParamsText;
        [SerializeField]
        private string _playerName;
        [SerializeField]
        private string _roomId;
        [SerializeField]
        private PlayerMatchmakingParameters _matchmakingParameters;
        [SerializeField]
        private string _expPlayers;
        [SerializeField]
        private int _searchAttmptsEditor;
        [SerializeField]
        private int _searchAttmpts;
        [SerializeField]
        private RankedDialogTest _dialogTest;
        [SerializeField]
        private RankedInfoViewTest _infoViewTest;
        [SerializeField]
        private RankedErrorDialog _errorDialog;
        [SerializeField]
        private bool _overrideParams;
        [SerializeField]
        private int _targetMMR;
        [SerializeField]
        private bool _selTesting;
    }
}

Usually this error is caused by the class name not matching the file name that contains it.
I have a full list of troubleshooting steps for that error.