if_http_client->request->set_cdata – Result Double quotes around entire body

I am trying to do a Web Service Call.  I am using if_http_client-Request->set_cdata and append_cdata2. 

The beginning and ending double quotes shouldn’t be included.  Any ideas of what needs to be changed to fix this? 

Below is the code that I tried

  wa_patch_body–keyfield = ‘NeverGonnaGiveYouUp’. 

CREATE OBJECT ref_json_serializer
    EXPORTING
      data = wa_patch_body.
  ref_json_serializer->serialize( ).
  g_body = ref_json_serializer->get_data( ).

*  ref_http_client->request->set_cdata(
*      exporting
*        data = g_body ).

ref_http_client->request->append_cdata2(
       exporting
         data = g_body ).

Both result in the follow results in Postman:

“{keyfield: “NeverGonnaGiveYouUp”}“