Iam getting error as 'oledbcommand' does not contain a definition for 'executenonqueryasync' and no extension method

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C#

WPF

Iam getting error as 'OleDbCommand' does not contain a definition for 'ExecuteNonQueryAsync' and no extension method 'ExecuteNonQueryAsync' accepting a first argument of type 'OleDbCommand' could be found (are you missing a using directive or an assembly reference?)

Its coming for both ExecuteNonQueryAsyncpre> and OpenAsyn

What I have tried:

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Data.OleDb;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ExcelElement
{
    public class Staff
    {
        public int CustomerID { get; set; }
        public string Name { get; set; }
        public string Email { get; set; }
        public string Size { get; set; }
        public string Address { get; set; }
    }
    class ExcelDataService
    {

        OleDbConnection Conn;
        OleDbCommand Cmd;


        public ExcelDataService()
        {
            string ExcelFilePath = @"C:\Users\Pulztec-3\Desktop\\book1.xlsx";
            string excelConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + ExcelFilePath + ";Extended Properties=Excel 12.0;Persist Security Info=True";
            Conn = new OleDbConnection(excelConnectionString);
        }

        /// <summary>  
        /// Method to Get All the Records from Excel  
        /// </summary>  
        /// <returns></returns>  
        /// 
        public async Task<ObservableCollection<Staff>> ReadRecordFromEXCELAsync()


        {
            
        ObservableCollection<Staff> Staffs = new ObservableCollection<Staff>();
         

            await Conn.OpenAsync();
            Cmd = new OleDbCommand();
            Cmd.Connection = Conn;
            Cmd.CommandText = "Select * from [Sheet1$]";
            var Reader = await Cmd.ExecuteReaderAsync();
            while (Reader.Read())
            {
                Staffs.Add(new Staff()
                {
                    CustomerID = Convert.ToInt32(Reader["CustomerID"]),
                    Name = Reader["Name"].ToString(),
                    Email = Reader["Email"].ToString(),
                    Size = Reader["Size"].ToString(),
                    Address = Reader["Address"].ToString()
                });
            }
            Reader.Close();
            Conn.Close();
            return Staffs;
        }

        /// <summary>  
        /// Method to Insert Record in the Excel  
        /// S1. If the EmpNo =0, then the Operation is Skipped.  
        /// S2. If the Student is already exist, then it is taken for Update  
        /// </summary>  
        /// <param name="Emp"></param>  
        public async Task<bool> ManageExcelRecordsAsync(Staff staff)
        {
            bool IsSave = false;
            if (staff.CustomerID != 0)
            {
                await Conn.OpenAsync();
                Cmd = new OleDbCommand();
                Cmd.Connection = Conn;
                Cmd.Parameters.AddWithValue("@CustomerID", staff.CustomerID);
                Cmd.Parameters.AddWithValue("@Name", staff.Name);
                Cmd.Parameters.AddWithValue("@Email", staff.Email);
                Cmd.Parameters.AddWithValue("@Size", staff.Size);
                Cmd.Parameters.AddWithValue("@Address", staff.Address);

                if (!IsStudentRecordExistAsync(staff).Result)
                {
                    Cmd.CommandText = "Insert into [Sheet1$] values (@CustomerID,@Name,@Email,@Size,@Address)";
                }
                else
                {
                    Cmd.CommandText = "Update [Sheet1$] set CustomerID=@CustomerID,Name=@Name,Email=@Email,Size=@Size,Address=@Address where CustomerID=@CustomerID";

                }
                int result = await Cmd.ExecuteNonQueryAsync();
                if (result > 0)
                {
                    IsSave = true;
                }
                Conn.Close();
            }
            return IsSave;

        }
        /// <summary>  
        /// The method to check if the record is already available   
        /// in the workgroup  
        /// </summary>  
        /// <param name="emp"></param>  
        /// <returns></returns>  
        private async Task<bool> IsStudentRecordExistAsync(Staff staff)
        {
            bool IsRecordExist = false;
            Cmd.CommandText = "Select * from [Sheet1$] where CustomerID=@CustomerID";
            var Reader = await Cmd.ExecuteReaderAsync();
            if (Reader.HasRows)
            {
                IsRecordExist = true;
            }

            Reader.Close();
            return IsRecordExist;
        }
    }
}