HTTP post request not returning valid data

[zaindroid]

Hi, I am trying to use this http client example but I am not able to visualize the data received, I am able to receive and parse JSON data on post request without header but when I add header , which is required for this one particular request the buffer shows no data , while param.message shows ?????? in terminal.

Following is my request format

`struct FetchParams dataStruct;
dataStruct.OnDataRcv =OnDataRcv;
dataStruct.method=Post;
Header headerContentType = {
.key="Content-Type",
.val="Application/json"

   };
   Header headerAuth = {
      .key="Authorization",
      .val=(char *)my_authCode
      //.val="Bearer 249174ddf663787f4ea605e5ef3c4996c03601543e5994a0d422adbe397c8d9e971560149708740"
      
   };
    
    dataStruct.header[0]=headerAuth;
    dataStruct.header[1]=headerContentType;
    char buffer[300];
    requestBody(clientId,authToken,buffer);
    dataStruct.body=buffer;
    fetch("https://api.test.fyta-app.de/hub/auth",&dataStruct);`

I have checked with postman , it returns the following output data

{
"access_token": "170ea98ce3fb4f7fc0955a3277e5f0ab9c9d3abad59b435553d36f11b0c81b2b731618926240929",
"token_type": "Bearer",
"expires_in": 86400,
"refresh_token": "17b52fd903fec46f884fa5a1431f30a7f5556663408b9a521bfa6437254731f4ec1618926240930",
"scope": "hub"
}

I am also attaching output on terminal,