The list of teams that represent your club will need to be added to the system in order for them to appear when creating Fixtures/Schedules/Events. It will be required also if you want to limit push notifications to specific teams.
If you are creating new Chat groups for communications you will need to make sure the Team is created as below before advancing to creating a new chat group.
Login to the Admin portal here
From the menu go to Club Settings -> Team Settings
Select the "Add a New Team" button to add a team to the list. To modify or delete a team select the Edit or Delete buttons from the Actions list.
Once the teams have been added they will appear in the notifications section when adding News/Fixtures/Schedules/Results.
More info on this process here.
For the supporter the team will appear in their Notification settings on the app where they can enable or disable notifications for this team.
More information on managing notifications here.