Actually when I log in to the Microsoft online login with this API https://login.microsoftonline.com/{tanent_id}/oauth2/v2.0/token and use the token response into this API headers https://graph.microsoft.com/v1.0/me/events to add an event into the outlook calendar then I found this kind of error.
Is this a token error? Or How to solve it? I am working on a React JS app to integrate outlook calendar.