可能是由于缺少必要的授权令牌或者权限不足导致的。可以尝试在调用API前加入必要的授权信息或者检查是否有足够的权限。示例代码如下：

import { AbpMultiTenancyService } from '@abp/multi-tenancy/abp-multi-tenancy.service';
import { impersonating } from '@abp/session/impersonating';
import { SubscriptionStartType } from '../../../../../src/shared/service-proxies/service-proxies';

export class MyServiceProxy {
  constructor(
    private http: HttpClient,
    private apiBaseUrlService: ApiBaseUrlService,
    private abpMultiTenancyService: AbpMultiTenancyService,
    private authService: AuthService
  ) {}

  get(url: string, params?: any) {
    return this.http.get(this.formatUrl(url), {
      headers: this.headers,
      params,
      withCredentials: true
    })
    .pipe(
      catchError(error => this.handleError(error)),
      tap(() => this.handleExceptions())
    );
  }

  private get headers() {
    let headers = {
      'Content-Type': 'application/json',
      'Pragma': 'no-cache',
      'Cache-Control': 'no-cache'
    };

    const authToken = this.authService.getAccessToken();
    if (authToken) {
      headers['Authorization'] = 'Bearer ' + authToken;
    }

    if (!this.abpMultiTenancyService.isEnabled) {
      return headers;
    }

    const multiTenancySide = this.abpMultiTenancyService.multiTenancySide;

    if (multiTenancySide == MultiTenancySides.HOST) {
      headers['Abp.TenantId'] = undefined;
      headers['X-Abp-Host-Tenant-Id'] = impersonating.tenantId;
    } else if (multiTenancySide == MultiTenancySides.TENANT) {
      headers['Abp.TenantId'] = impersonating.tenantId;
      headers['X-Abp-Host-Tenant-Id'] = undefined;
    }

    return headers;
  }

  private formatUrl(url: string):