Why is ID 0 returned after WidgetMediatopicPost?

Question

API

In general, I did everything as in the API docs . Once a post came to my wall, the next time, the result is returned to me:
"type":"success"
"id":"0"
"signature":"830ea94bd72b863b8dc1295f9691c515"
Mabbe error in the code?

$snip = '{
      "media": [
        {
          "type": "text",
          "text": "Genetic-test"
        },
        {
          "type": "photo",
          "list": [
            {
              "photoId": "802457834754"
            }
          ]
        }
      ]
    }';

    $snip = str_replace(' ', '', $snip);
    $snip = str_replace("\t", '', $snip);
    $snip = str_replace("\n", '', $snip);
    $snip = str_replace("\r", '', $snip);

    $secretKey = 'тут мой secret app key';
    $returnURL = 'http://sergeylutov.ru/ok/';

    $resultMD5 = md5("st.attachment=" . $snip . "st.return=" . $returnURL . $secretKey);

<a href='http://connect.ok.ru/dk?st.cmd=WidgetMediatopicPost
    &st.app=1138994432
    &st.attachment=<? echo $snip ?>
    &st.signature=<? echo $resultMD5 ?>
    &st.return=<? echo $returnURL ?>
    &st.popup=off
    &st.silent=on
    &st.utext=off
  '>test</a>

Answer 1

Perhaps because the application needs to be approved.
Second paragraph https://apiok.ru/wiki/pages/viewpage.action?pageId...