Saving post api data

public string AuthoryOfCertificate { get; set; }
public TimeSpan EstManHour { get; set; }
public string DefectDamage { get; set; }
public TimeSpan ActualManHour { get; set; }

public List<MaterialDetail> mmaterial { get; set; }

public List<ToolsDetailData> ttools { get; set; }

public async void SaveNRC()
{
    CreateNRCMainClass obj = new CreateNRCMainClass();
    obj.CustomerName = AriregnCustomerName;
    obj.AircraftModel = AircraftModel;
    obj.AircraftRegn = aircraft;
    obj.AUTHNo = AUTHCERT;
    obj.Date = DateTime.Now;
    obj.FindingfromTask = FindingTaskData;
    obj.ATA = ATAData;
    obj.SUBATA = SubATA;
    obj.ZoneTrade = ZoneData;
    obj.TradeToAction = TradeToactionData;
    
    List<MaterialDetail> materialsobj =  DependencyService.Get<ISQLMaterialAndTools>().GetMyMaterials();
           
    List<ToolsDetailData> toolsDetailsobj = DependencyService.Get<ISQLMaterialAndTools>().GetTools();

    string objectdata = JsonConvert.SerializeObject(obj);
    WorkOrderApiHelper _workOrderApiHelper = new WorkOrderApiHelper();
    var data = await _workOrderApiHelper.SaveNRCToolAndMaterialData(obj);
    DependencyService.Get<ISQLMaterialAndTools>().SaveNRCMain(obj);
}