HTTP Get Response into variable (fv!result not found)

Hello, 

I am trying to save the HTTP GET response value into a variable in UI and I am getting an error when trying to parse '"fv!result" on a!httpResponse. 

I am trying to access the value inside "body" from the attached screenshot. Below is the code that I have been using to access the result: 

 saveInto:{
            rule!EXP_BPM_SC1_Calculate_Experience_API(
              lineId:  ri!expediteline.request_line_id,
             ssd:  ri!expediteline.new_scheduled_ship_date,
              role: "SC1",
              onSuccess: {
                 a!httpResponse(
                   statusCode: 200,
                   headers: {
                   a!httpHeader(name: "Content-Type", value: "application/json")
                            },
                  body: a!toJson_17r1(fv!result)
                   ),
                a!save(local!apiResult,fv!result)
              }
            )
          }

Thanks