Unfortunately Mio Universal Channels will only work on paid versions of Microsoft Teams.
The free version of Microsoft Teams doesn't include all of the scopes needed for the app to successfully send messages from one platform to another.
Try an alternative option:
Have another Microsoft account?
Try re-installing Mio using a corporate email rather than a hotmail, gmail, or other personal email.
Don't have another Microsoft account?
Microsoft requires you or your Teams admin to upgrade in order to use third-party apps like Mio. You may be eligible for a trial.
Not sure what to do?
We can help! Schedule a 15-minute support call to get personalized assistance. This is recommended if you're testing or were invited to join a universal channel.