I'm facing on the same/similar issue with this issue.
I tried to publish my python package "hippos" to PyPI, but it failed with the error of this PR title even though that name doesn’t seem to exist in PyPI. Could you please help me?🙏
Btw, I actually first tried to register using the name "cat", but that gave me the same error. And really, if I can use ”cat”, I might want to use "cat". Anyways, sorry, for now, I'm happy if I would be able to register it under the name "hippos" first 🙇 (For now, I already had registered under the name "Cattt" because I needed to register in a hurry.)