To delete a team, go to the Team Settings link under the menu icon in the top-right corner of the app.
Then, locate the name of the team you would like to delete. Click the three dots to the right of that group's row and select Delete Teams.
You'll be presented with a confirmation window that will ask you to confirm that you'd like to delete this team.
Click Confirm to delete the team.
To learn how to delete a user, click here.