API를 통해 새 주제를 생성할 수 없음

API를 사용하여 API 토큰을 생성했는데, 인증 리다이렉트 후 응답이 다음과 같습니다:
{
api = 4;
key = bd0553a26566b6ace74869ad6042fc22;
nonce = “5A3D2DD2-D6E3-4539-BDE1-3F114B9EC3A1”;
push = 0;
}

이후 다음과 같이 API를 사용하여 새 게시물을 생성하려고 합니다:

---REQUEST------------------
URL: https://myserver.com/posts.json
METHOD: POST
Api-Key: bd0553a26566b6ace74869ad6042fc22
Content-Type: application/json
Api-Username: AndrewB
BODY: {
  "title" : "Test topic",
  "raw" : "This is posted from the API",
  "category" : 0
}
----------------------------

하지만 잘못된 접근 오류가 발생합니다:

---RESPONSE------------------
URL: https://myserver.com/posts.json
MIMEType: application/json
Status Code: 403
Content-Type: application/json; charset=utf-8
x-runtime: 0.006244
Content-Encoding: gzip
Server: nginx
x-download-options: noopen
x-xss-protection: 1; mode=block
x-permitted-cross-domain-policies: none
referrer-policy: strict-origin-when-cross-origin
Date: Tue, 31 Mar 2020 17:37:54 GMT
x-request-id: 82b293d8-a609-42b1-8338-dcbdcbc72a61
x-content-type-options: nosniff
x-frame-options: SAMEORIGIN
Vary: Accept-Encoding
Response Data: {"errors":["You are not permitted to view the requested resource. The API username or key is invalid."],"error_type":"invalid_access"}
Response JSON: {
    "error_type" = "invalid_access";
    errors =     (
        "You are not permitted to view the requested resource. The API username or key is invalid."
    );
}
----------------------------

사용자 계정은 다음과 같습니다:

관리자 API 섹션:


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