ErrorInvalidIdMalformed — Malformed ID

An ID you provided to Graph is malformed or in the wrong format. For instance, using an Outlook item ID in the wrong context can cause this. If you're using Riposte's message or event IDs, stick with those as they are properly formatted. If you're manually specifying Graph IDs, ensure they are exactly as returned by Graph (including base64 encodings for certain IDs). Correct the ID format and retry the request.