Microsoft Graph StatusCode 401 Unauthorized SendMail 365

Question

Hi team,

Im trying to send emails to Office 365 using Microsoft Graph with C# Entity Framewrok 4.6.2.

I can get the token but when I invoke the SendMail method I receive a 401Unauthorized error.

This is my code:

var response = httpClient.PostAsync("https://graph.microsoft.com/v1.0/users/45626e13-1e46-48a0-a1df-812b4e5194fc/sendmail ", content).Result; ; //HERE IS ERROR 401 !!!!!!!!!!!!!!