send post in wordpress with flutter

hi i want to send post to wordpress with api in flutter and i use JSON API and JSON API USER Plugin to get api.

when i want to send post with api i got error

{
    "status":"error",
    "error":"You need to login with a user that has 'edit_posts' capacity."
}

this is my code:

Future<http.Response> sendTahlil(_title, _content) async {
  final response = await http.get(
    "https://example.com/api/get_nonce/?controller=posts&method=create_post",
  );

  var decodedjson = jsonDecode(response.body);
  // String nonCode = jsonDecode(decodedjson['nonce']);
  var urlcreat =
      "https://example.com/api/posts/create_post/?nonce=${decodedjson['nonce']}&title=${_title}&content=${_content}";
  final ressend = await http.post(
    urlcreat,
  );
  print(ressend.body);
  print("OOOOOKKKKK");
}