var bpsResponseXml = new XElement("BPSResponse");

bpsResponseXml.Add(new XElement("Response",
                                    new XElement("Code", "804"),
                                    new XElement("Text", "TagID value is not genuine")));

var outPutXml = bpsResponseXml.Value;

<BPSResponse>    <Response>      <Code>804</Code>      <Text>TagID value is not genuine.</Text>    </Response>  </BPSResponse>

<BPSResponse><Response><Code>804</Code><Text>TagID value is not genuine.</Text></Response></BPSResponse>

var bpsResponseXml = new XElement("BPSResponse");

bpsResponseXml.Add(new XElement("Response",
                                    new XElement("Code", "804"),
                                    new XElement("Text", "TagID value is not genuine")));

var outPutXml = bpsResponseXml.ToString(System.Xml.Linq.SaveOptions.DisableFormatting);