To troubleshoot please check:
Do you sit behind a corporate firewall, or are you in a public setting like a coffee shop? If you aren't able to install other packages from npmjs.com, it might be a firewall or proxy issue.
Are you running
npm install -g @haiku/clifrom a directory that has an
.npmrcfile? Try running the command from a different directory.
npm cache clear -f
Has the default registry been adjusted? Try
npm set registry https://registry.npmjs.org/to reset it.
Finally, try a full reset of NPM and deleting the root