Aptos update failed

C:\Users\Administrator>aptos update
{
  "Error": "Unexpected error: Failed to fetch releases: NetworkError: api request failed with status: 403 - for: \"https://api.github.com/repos/aptos-labs/aptos-core/releases\""
}

Why does this error show me when I execute ‘aptos update’ in terminal on windows?
Please help me.