I have application registered in Azure Active directory, we use app id and secret to access different resources, here is sample code to request access token

```
var authority = $"https://login.windows.net/TENANT_ID";
var authContext = new AuthenticationContext(authority, TokenCache.DefaultShared);
var clientCred = new ClientCredential("APP_ID", "APP_SECRET");
var result = await authContext.AcquireTokenAsync("RESOURCE_ID", clientCred);
Console.WriteLine(result.AccessToken);

```

However one of the systems requires us to include UPN in access token, is it possible? Is it possible to assign some UPN to Application?