I can't use CCG for a paid account

Its possible you are sending in the wrong information from what is expected. Can you check your app access selection as started here? If you update it, don't forget you'll need to reauthorize the application in the admin console afterwards. 

Alex, Box Developer Advocate

395005653353

Here are my app settings

Right - so it looks like you have it set to app access only, which means you'll need to follow the below instructions on what you sent in.

If you would like to authenticate as the application's Service Account:

• set box_subject_type to enterprise
• set box_subject_id to the enterprise ID

My account is not a service account.  I used https://developer.box.com/guides/authentication/client-credentials/ for the Managed User use case and it did not work.

If you would like to authenticate as a Managed User:

• set box_subject_type to user
• set box_subject_id to the user ID

So in order to use user in the subject type you will want to change the app access to app + enterprise access. 

While your account is not a service account, a service account is automatically created for any ccg/jwt applications after admin authorization. 

395005653353, I tried and ticked all the checkboxes but no luck