To delete a team, you'll need to remove all the members from the team.
1) Navigate to the campaign's admin panel.
2) Click on the People tab and Teams tab under it.
3) Find the team to delete from the list and click/dbl-click on the record.
4) Click Edit button on the pop-up.
5) Dbl-Click on the each member on the members list.
6) Click Edit button on members pop-up.
7) Scroll down to Team Info section and uncheck the "In Team" checkbox to remove the member from the team.
8) Click Save button on the members pop-up to save the changes.
9) Follow steps 5-8 for each member.
10) Click on the Save button on the team pop-up.
11) If the changes don't show, refresh the page to see the changes.
Note : If you have "Allow teams without members" selected in the campaign settings, removing all the members is not enough. You have to also delete the team. Click on the icon and select Delete option to delete the team.