I am able to get a token from the Graph API using an OAuth2 account client credentials, but when I go to use that with an http client snap, I get a 401 - Unauthorized from the endpoint error message. The snap adds the access token to the endpoint like: https://graph.microsoft.com/v1.0/users/<mailbox_email>/sendMail?access_token=<tokenguid>
I am able to use the same client application to send emails with the same mailbox in Postman.
Looking at the error in debug, it says my access token is empty. Do I need to change something in the account to fix that?