Sending Mail Using Microsoft Graph Rest

Summary

Graph token generation fail using authent 2.0

Content

Hi all,

I try to create an Endpoint to send Mail using oulook tenant and Graph rest API, when testing I've got the Following errors :

{
    "type": "HTTP://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.1",
    "status": 401,
    "title": "Unauthorized",
    "detail": "{\"error\":{\"code\":\"InvalidAuthenticationToken\",\"message\":\"Access token is empty.\",\"innerError\":{\"request-id\":\"37c20b92-43d7-4030-8dbe-41eba5829cce\",\"date\":\"2020-04-07T17:09:48\"}}}"
} 

Thank You in advance for your support

Code Snippet

{
    "swagger": "2.0",
    "info": {
        "title": "V1.0 Me",
        "x-vb": {
            "dt-serviceAuthentication": {
                "type": "client_cred_oauth",
                "clientIdCredentials": "oracle_custom_c8977bc6-d686-",
                "scope": "Mail.Send",