Ionic invalid-http-status-code-405

Nao consigo acessar os dados da APi que me foi passada via app
Erro:Response for preflight has invalid HTTP status code 405
Codigo:
getUsers(code: string) {

this.headers = new Headers();
this.headers.set('Accept', 'application/ json; charset = utf - 8')
this.headers.append('Content-Type', 'application/ json; charset = utf - 8')
this.headers.append('Access-Control-Allow-Origin')

return new Promise(resolve => {

  console.log(
    code);

  this.http.post(this.apiUrl, code, { headers: this.headers })

    .map(res => res.json())
    .subscribe(data => {
      data = data;
      resolve(data);
    });