Hi, @ckwiat46  I just modified a little bit of your code, can you please try the below code?

using Newtonsoft.Json;
using PX.Data;
using PX.Data.Webhooks;
using PX.Objects.IN;
using System;
using System.Net.Http;
using System.Threading;
using System.Threading.Tasks;
using System.Web.Http.Results;

namespace WebHooksConfiguration
{
    public class ObjectInventoryItemJSON
    {
        public string InventoryId { get; set; }
        public string Description { get; set; }     
    }
    public class KWInsInventoryItemSync : IWebhookHandler
    {
        public async Task<System.Web.Http.IHttpActionResult> ProcessRequestAsync(
       HttpRequestMessage request, CancellationToken cancellationToken)
        {
            using (var scope = GetAdminScope())
            {
                if (request.Method == HttpMethod.Post)
                {
                    string jsonContent = request.Content.ReadAsStringAsync().Result;

                    var obj = JsonConvert.DeserializeObject<ObjectInventoryItemJSON>(jsonContent);

                    if (obj != null)
                    {
                        using (var ts = new PXTransactionScope())
                        {
                            ProcessData(obj.InventoryId, obj.Description);

                            ts.Complete();
                        }
                    }
                }
            }

            return new OkResult(request);
        }

        public void ProcessData(string InventoryId, string Description) 
        {
            if (!string.IsNullOrEmpty(InventoryId))
            {
                 var graph = PXGraph.CreateInstance<NonStockItemMaint>();
                                    InventoryItem newItem = PXSelect<InventoryItem, Where<InventoryItem.inventoryCD, Equal<Required<InventoryItem.inventoryCD>>>>.Select(Base,inventoryid.Trim());


                if (newItem != null)
                {
                    graph.Item.Current = newItem;
                }
            }
        }      
        private IDisposable GetAdminScope()
        {
            var userName = "admin";
            if (PXDatabase.Companies.Length > 0)
            {
                var company = PXAccess.GetCompanyName();
                if (string.IsNullOrEmpty(company))
                {
                    company = PXDatabase.Companiese0];
                }
                userName = userName + "@" + company;
            }
            return new PXLoginScope(userName);
        }
    }
}

Hello @Naveen Boga i tried the code you suggested but still facing same issue.

//at this place we are getting error.
graph.Item.Current = newItem;

Hi @ckwiat46 were you able to find a solution? Thank you!