Power BI admin api returns 401 unauthorized

Hello,
I’m trying to make queries through the Power BI Service APIs, but I find that I can’t with any of the Power BI REST APIs: https://api.powerbi.com/v1.0/myorg/admin/
With any other API, such as https://api.powerbi.com/v1.0/myorg/groups/{{workspace}}/reports
no problem, but I can’t get admin. I’ve checked that the user is admin, fabric admin. I’ve tested with the o365 admin user, the fabric admin, and the Power BI admin, and I always get a 401 Unauthorized.
I’m getting the token through Get new access token with user/pwd along with client id and client secret.

The Azure app is within a security group that is also allowed to use the Power BI API. The app also has permissions granted to perform queries, and I don’t know what else to check.
Has the same thing happened to anyone?