How do I solve this "specified value has invalid CRLF characters"?

    Dim url = "https://gold.mxpress2u.net/gold/API.asmx"
    Dim httpRequest = CType(WebRequest.Create(url), HttpWebRequest)
    httpRequest.Method = "POST"
    httpRequest.ContentType = "application/xml"
    httpRequest.Accept = "application/xml"

    Dim data = Me.txtXML.Text
    httpRequest.Headers("strAPIKey") = "API Key"
    httpRequest.Headers("strCustomerAccount") = "Account No"
    httpRequest.Headers("intPrintFormatType") = "1"
    httpRequest.Headers("strShipmentDetailsXML") = data

'' After debug the error is on this "httpRequest.Headers("strShipmentDetailsXML") = data"
'' Error is System.ArgumentException: 'Specified value has invalid CRLF characters.

    Dim streamWriter = New StreamWriter(httpRequest.GetRequestStream())
    If True Then
        streamWriter.Write(data)
    End If
    Dim httpResponse = CType(httpRequest.GetResponse(), HttpWebResponse)
    Dim streamReader = New StreamReader(httpResponse.GetResponseStream())
    If True Then
        Dim result = streamReader.ReadToEnd()
    End If
    Console.WriteLine(httpResponse.StatusCode)

<xml><ServiceTypeID>1</ServiceTypeID><ShipperContactPerson>padhma</ShipperContactPerson><ShipperCompanyName>Jetpharma Sdn Bhd</ShipperCompanyName><ShipperPhoneNumber>03-8076 1651</ShipperPhoneNumber><OriginCountryID>1</OriginCountryID><OriginStateID>12</OriginStateID><OriginPostcode>47000</OriginPostcode><OriginCity>Bandar Puchong Jaya</OriginCity><OriginAddress>1, 11 & 13, Jalan Rajawali 2, Bandar Puchong Jaya, 
47100 Puchong, Selangor</OriginAddress><RecpContactPerson>contact Person</RecpContactPerson><RecpCompanyName>Azam Bekal Enterprise</RecpCompanyName><RecpPhoneNumber>0146675956</RecpPhoneNumber><DestCountryID>1</DestCountryID><DestStateID>11</DestStateID><DestPostcode>45000</DestPostcode><DestCity>Ipoh</DestCity><DestAddress>Farmasi Azam No. 6, Jalan Cindai Jaya 1, Taman Cindai Jaya, 08000 Sungai Petani, Kedah. 08000</DestAddress><Description>small package</Description><Remarks>Remarks</Remarks><Pieces>6</Pieces><Weight>0.00</Weight><Length>1.00</Length><Width>1.00</Width><Height>1.00</Height><CODAmount>0.00</CODAmount><ReferenceNumber>SO-1298712</ReferenceNumber></xml>