Change library from public to private

I have a public library that was created on that administrator account, I transferred it to a user and now want to make said library private but have not been able to find out how to do this. Googling got me to the Web API documents that seem to make this possible. Is there an easier way?

I think this is not possible if this library was/is public.


I’m trying the Web API but I can’t get the Token, it just don’t accept my credentials despite being able to login with them just fine on the web interface.

Managed to get the Token and Repo-Id, upon executing the command to change the library type I only get permission denied.