Connector SOAP without external task or java class

Hi I am using following way to call web service endpoint but not working.
Input
Url: Text =TempConvert Web Service
payload: Script , Script Format: freemaker, Source Type: Inline Script
Script = <soap12:Envelope xmlns:xsi=“http://www.w3.org/2001/XMLSchema-instance” xmlns:xsd=“http://www.w3.org/2001/XMLSchema” xmlns:soap12=“http://www.w3.org/2003/05/soap-envelope”>

soap12:Body

<FahrenheitToCelsius xmlns="https://www.w3schools.com/xml/">

  <Fahrenheit>75</Fahrenheit>

</FahrenheitToCelsius>

</soap12:Body>

</soap12:Envelope>

headers: Map = text/xml

I am not using any external delegate or java class
. I am trying to do this within camunda. Please let me know if anyone have done this.