Deserialize dates in dd/MM/yyyy format using Newtonsoft JSON in ASP.Net

I have issue in date format. I have selected from date and to date.

Date is 2021-04-01 to 2021-04-15. But Json shows 1/4/2021. insert data from Json to Mssql table, it pickup date 4 and month from Jan to Dec.

Not showing April only

Below is my code

Public Class data_biz_trak
     Public Property docno As String
     Public Property docdate As String
     Public Property custcode As String
     Public Property custname As String
     Public Property MarketingExe As String
     Public Property Transporter As String
     Public Property cnno As String
     Public Property SoNo As String
     Public Property invNo As String
     Public Property amount As Decimal
 End Class

Private Sub InsertData_BizTrak_Range()
    Dim url As String = "http://localhost:57919/testurl/WebService.asmx/GetBizTrak_Data_Range?strfrom=2021-04-01&strto=2021-04-15"
    ServicePointManager.Expect100Continue = True
    ServicePointManager.SecurityProtocol = CType(3072, SecurityProtocolType)
    Dim json As String = (New WebClient).DownloadString(url.TrimEnd())
    Dim res As List(Of data_biz_trak) = JsonConvert.DeserializeObject(Of List(Of data_biz_trak))(json)
 
    For Each data_biz_trak In res
 
        Dim cmd As New SqlCommand
        cmd.Connection = conn
        cmd.CommandType = CommandType.StoredProcedure
        cmd.CommandText = "usp_API_BizTrak"
        cmd.Parameters.Add(New SqlParameter("@Action", "INSERT-BIZTRAK-DATA"))
 
        cmd.Parameters.AddWithValue("@docno", data_biz_trak.docno)
        cmd.Parameters.AddWithValue("@docdate", data_biz_trak.docdate)
        cmd.Parameters.AddWithValue("@custcode", data_biz_trak.custcode)
        cmd.Parameters.AddWithValue("@custname", data_biz_trak.custname)
        cmd.Parameters.AddWithValue("@MarketingExe", data_biz_trak.MarketingExe)
        cmd.Parameters.AddWithValue("@Transporter", data_biz_trak.Transporter)
 
        cmd.Parameters.AddWithValue("@cnno", data_biz_trak.cnno)
        cmd.Parameters.AddWithValue("@SoNo", data_biz_trak.SoNo)
        cmd.Parameters.AddWithValue("@invNo", data_biz_trak.invNo)
        cmd.Parameters.AddWithValue("@amount", data_biz_trak.amount)
 
        Dim da As New SqlDataAdapter(cmd)
        Dim dt As New DataTable
        da.Fill(dt)
 
        cmd.Parameters.Clear()
        cmd.Dispose()
    Next
End Sub

selected date from 2021-04-01 to 2021-04-15 Json Format

[{"docno":"275","docdate":"2/4/2021","custcode":"63","custname":"Ut Consulting","MarketingExe":"Lester","Transporter":"Conubia LLC","cnno":"7725","SoNo":"5136","invNo":"4660","amount":15136.00},
{"docno":"330","docdate":"2/4/2021","custcode":"11","custname":"Proin Ltd","MarketingExe":"Kyla","Transporter":"Mauris Institute","cnno":"5836","SoNo":"5145","invNo":"4747","amount":16575.00},
{"docno":"669","docdate":"3/4/2021","custcode":"38","custname":"Neque Sed Eget Corp.","MarketingExe":"Boris","Transporter":"Dictum Proin Eget Foundation","cnno":"8122","SoNo":"5463","invNo":"4759","amount":15607.00},
{"docno":"225","docdate":"3/4/2021","custcode":"76","custname":"Aliquam Associates","MarketingExe":"Keelie","Transporter":"Dictum Ultricies Ligula Inc.","cnno":"6805","SoNo":"5372","invNo":"4692","amount":10268.00},
{"docno":"337","docdate":"10/4/2021","custcode":"64","custname":"Ipsum Leo Elementum LLP","MarketingExe":"Natalie","Transporter":"Consectetuer Institute","cnno":"3244","SoNo":"5056","invNo":"4985","amount":32854.00},
{"docno":"270","docdate":"10/4/2021","custcode":"100","custname":"Luctus Ipsum Leo Ltd","MarketingExe":"Calvin","Transporter":"Sed Inc.","cnno":"9991","SoNo":"5337","invNo":"4545","amount":33128.00},
{"docno":"718","docdate":"11/4/2021","custcode":"32","custname":"At Institute","MarketingExe":"Brenden","Transporter":"Lectus Corp.","cnno":"9636","SoNo":"6283","invNo":"4644","amount":29917.00},
{"docno":"401","docdate":"12/4/2021","custcode":"49","custname":"Faucibus Morbi Industries","MarketingExe":"Yvette","Transporter":"Non Corporation","cnno":"5584","SoNo":"6258","invNo":"4890","amount":27515.00},
{"docno":"437","docdate":"12/4/2021","custcode":"90","custname":"Malesuada Fames Industries","MarketingExe":"Wylie","Transporter":"Morbi Consulting","cnno":"7751","SoNo":"5627","invNo":"4707","amount":30748.00},
{"docno":"224","docdate":"13/4/2021","custcode":"53","custname":"Id Ante Dictum Institute","MarketingExe":"Nomlanga","Transporter":"Quam Limited","cnno":"3115","SoNo":"5445","invNo":"4990","amount":34503.00},
{"docno":"498","docdate":"13/4/2021","custcode":"13","custname":"Ullamcorper Viverra Maecenas Institute","MarketingExe":"Robert","Transporter":"Nunc Ullamcorper Corp.","cnno":"3475","SoNo":"6294","invNo":"4541","amount":33408.00},
{"docno":"528","docdate":"14/4/2021","custcode":"60","custname":"Leo In Lobortis Ltd","MarketingExe":"Simone","Transporter":"Duis Volutpat LLP","cnno":"5182","SoNo":"5150","invNo":"4991","amount":30648.00},
{"docno":"210","docdate":"14/4/2021","custcode":"51","custname":"Tempus Lorem Fringilla LLC","MarketingExe":"Tanek","Transporter":"Ante Ipsum Consulting","cnno":"7779","SoNo":"5100","invNo":"4625","amount":30068.00},
{"docno":"223","docdate":"15/4/2021","custcode":"42","custname":"Ornare Lectus Justo PC","MarketingExe":"Tyler","Transporter":"Bibendum Corporation","cnno":"6442","SoNo":"5014","invNo":"4788","amount":30851.00}]

Please advice me

Thank you in advance

Maideen