Unity error CS0273 please tell me how to fix it

using RiptideNetworking;
using RiptideNetworking.Utils;
using UnityEngine;

public class NetworkManager : MonoBehaviour
{
    private static NetworkManager _singleton;

    private static NetworkManager Singleton
    {
        get => _singleton;
        private set
        {
            if (_singleton == null)
                _singleton = value;
            else if (_singleton != value)
            {
                Debug.Log($"{nameof(NetworkManager)} instance already exists, destroying duplicate!");
                Destroy(value);
            }
        }
    }

    public Server Server { get; private set; }

    [SerializeField] private ushort port;
    [SerializeField] private ushort maxClientCount;

    private void Awake()
    {
        Singleton = this;
    }

    private void Start()
    {
        RiptideLogger.Initialize(Debug.Log, Debug.Log, Debug.LogWarning, Debug.LogError, false);

        Server = new Server();
        Server.Start(port.maxClientCount);
    }


    private void FixedUpdate()
    {
        Server.Tick();
    }


    private void OnApplicationQuit()
    {
        Server.Stop();
    }
}

It said I’m wrong on this line:
private set

Here is the problem:
The accessibility modifier of the ‘NetworkManager.Singleton.set’ accessor must be more
restrictive than the property or indexer ‘NetworkManager.Singleton’

Please tell me how to fix this?

>Solution :

You should remove the "private" on the set accessor, because the property is already private.

ref: accessor must be more restrictive than the property or indexer