Integrate quip with Salesforce

Hello all,

I am trying to integrate quip to my salesforce org. Firstly, I tried integrating using "Quip for free" but it is showing "This site name is not available" for whatever the sitename I give.

Secondly, I have created an account in quip. But when I try to add the site's subdomain it is throwing an error - "We couldn’t connect your Quip site. Log in to the Quip Admin Console to see what went wrong. Not Found" 

Also, I am unable to login to admin console even though I have an option named 'admin' when I click upon my Profile in quip. Should I have any quip license for admin console?

Can anyone please explain how to resolve these issues?

Thanks in advance.