Adobe PDF Services API Free Tier is not available

I want to use the Adobe PDF Services API Free Tier, but I get the following message as shown in the capture. I am an Enterprise Admin, so I tried to set it up from the Admin Console, but I don’t know how to do it.

You don’t have access to PDF Services API Your account is currently associated with an Enterprise which does not have access to PDF Services API. For Free Tier please sign up with a different personal account If you want to create production credentials please contact your Enterprise Admin or Contact us.

In addition, due to the circumstances of the linked system, I cannot verify it with a personal account.