Full Code

BackendGameLog.cs

using System.Collections.Generic;
using System.Text;
using UnityEngine;

// Adds BACKND SDK namespace
using BackEnd;

public class BackendGameLog {
    private static BackendGameLog _instance = null;

    public static BackendGameLog Instance {
        get {
            if(_instance == null) {
                _instance = new BackendGameLog();
            }

            return _instance;
        }
    }

    public void GameLogInsert() {
        Param param = new Param();

        param.Add("clearStage", 1);
        param.Add("currentMoney", 100000);

        Debug.Log("Attempting to insert game log.");

        var bro = Backend.GameLog.InsertLog("ClearStage", param);

        if(bro.IsSuccess() == false) {
            Debug.LogError("An error occurred while inserting the game log. : " + bro);
            return;
        }

        Debug.Log("Successfully inserted game log. : " + bro);
    }
}

BackendManager.cs

using UnityEngine;
using System.Threading.Tasks;

// Adds BACKND SDK namespace
using BackEnd;

public class BackendManager : MonoBehaviour {
    void Start() {
        var bro = Backend.Initialize(true); // Initialize BACKND

        // Response value for BACKND initialization
        if(bro.IsSuccess()) {
            Debug.Log("Initialization successful : " + bro); // If successful, 'statusCode 204 Success'
        } else {
            Debug.LogError("Initialization failed : " + bro); // If failed, a 4xx statusCode error occurs 
        }

        Test();
    }

    // A method that allows synchronous methods to be called from asynchronous methods(cannot be accessed by the Unity UI)
    async void Test() {
        await Task.Run(() => {
            BackendLogin.Instance.CustomLogin("user1", "1234");

            BackendGameLog.Instance.GameLogInsert(); // [Addition] Function for saving game logs
            
            Debug.Log("Test complete.");
        });
    }
}

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