Microsoft Graph API Delegated access

Hi all,
I’ve followed through the instructions at Use Postman with the Microsoft Graph API - Microsoft Graph | Microsoft Learn to get Postman connected with my Azure app registration. I’m running into the following issue when trying to generate a new access token for Delegated permissions.

Error: invalid_client, Description: AADSTS700025: Client is public so neither ‘client_assertion’ nor ‘client_secret’ should be presented

Upon clicking the Generate new access token button I’m taken into the sign-in url for my org which succeeds but then makes the call out to /oauth2/v2.0/token which fails with the above message. Any ideas?