Team Work
There must be something that you have done in your life that involves interacting with other people?
What do you do at work? What did you do at school or university? Were you involved in any clubs or societies? Even organising a holiday for a group of friends might count as working as a team if you can gloss it up a bit.
Don't necessarily think you have to have been the captain of the football team for successful stories of team membership.
Best of luck