We are building a web app that needs to send instant messages to people's Teams channel. I tried to use the webhook first but it requires a business/school account. However we need this to work for personal accounts too. So I changed to use the REST/Graph API. I've managed to grab access token using oauth2.
Can you please point out which API should I be using for getting people's connected teams and channels and sending messages to them?
The trouble I'm getting is whenever I make a request to /me/joinedTeams (with the correct access token obtained via oauth), I receive an error saying ResourceNotFound. Do you have any idea why? The account I used for testing doesn't have office 365 subscription but has Microsoft Teams activated.