我正在学习this教程，将AWS Amplify集成到iOS中。我添加了GraphQl API后端，但是当我尝试将其推送到云端时，我得到了这个错误：

❯ amplify push
⠙ Fetching updates to backend environment: dev from the cloud.(node:75854) UnhandledPromiseRejectionWarning: AccessDenied: Access Denied
    at Request.extractError (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/services/s3.js:831:35)
    at Request.callListeners (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/sequential_executor.js:106:20)
    at Request.emit (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/sequential_executor.js:78:10)
    at Request.emit (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/request.js:683:14)
    at Request.transition (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/request.js:22:10)
    at AcceptorStateMachine.runTo (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/state_machine.js:14:12)
    at /usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/state_machine.js:26:10
    at Request.<anonymous> (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/request.js:38:9)
    at Request.<anonymous> (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/request.js:685:12)
    at Request.callListeners (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/sequential_executor.js:116:18)
(node:75854) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:75854) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
⠇ Fetching updates to backend environment: dev from the cloud.

然后它挂起，我必须Ctrl-C来摆脱它。我尝试通过运行amplify configure来排除AWS CLI环境的故障，然后按照提示创建新用户。新用户将AdministratorAccess策略附加到其权限，但仍出现相同的AccessDenied错误。