How to get in contact with an owner of a namespace?


As part of a company I would like to get a namespace that reflect the company name. The namespace is pt. taken and I assume it is a ex-employee that created the namespace. I tried to write a message (comment) in the namespace, hoping the person would contact me, but no response.
There has been no commits to the repo during in the past year so it is not in use.

How do get in contact with an owner of the namespace? Meaning - how do i get the name or e-mail of the owner of the namespace?