Access to Partner Center through Rest APIs or Connector

Dear Team,

I'm trying to access Partner Center via REST API/.NET Client or using a connector within Power Automate/Azure Logic Apps. Unfortunately, all authentication attempts are being rejected, often returning a 403 status without any response body.

For context, I have already added my service principal to the Partner Center account with the Admin Agent role for customers.

Additionally, I attempted to authenticate using the MCP connector available in Logic Apps and Power Automate, but I received a message stating that admin consent from Microsoft is required. Both apps shown for consent are not under my tenant, which is blocking further progress.

Could you please advise on the correct approach or any necessary configurations to enable API access for my scenario?

Thank you!