Here is the code you asked for in this issue.
public async Task<object> Read(FaxReadType faxReadType) { object returnData = null; try { using (RestClient rc = new RestClient(RINGCENTRAL_CLIENTID , RINGCENTRAL_CLIENTSECRET , IS_PRODUCTION)) { TokenInfo tokenInfo = await rc.Authorize(RINGCENTRAL_USERNAME , RINGCENTRAL_EXTENSION , RINGCENTRAL_PASSWORD); if (rc.token.access_token.Length > 0) { switch (faxReadType) { case FaxReadType.ReadContent: ReadMessageContentParameters read = new ReadMessageContentParameters { contentDisposition = "Attachment" }; returnData = await rc.Restapi().Account().Extension() .MessageStore(messageId).Content(attachmentId).Get(read); break; case FaxReadType.ReadMessage: returnData = await rc.Restapi().Account().Extension() .MessageStore(messageId).Get(); break; } } } } catch (Exception ex) { //Log exception in DB } return returnData; }