checked the lookup and existing teams but there is no team name called Sample, I am not able to complete this module https://org62.my.trailhead.com/content/employee/modules/gus_work/gus_see_big_picture?trail_id=gus_trail&trailmix_creator_id=jjuett&trailmix_slug=bootcamp-week-1-pre-work-agile-salesforce
For anyone else facing this issue - I came across this issue as well. I did not add a Product tag and attempted to create the new team - "Sample". So, i believe it was a partial transaction and it did not rollback at the back-end, so I was not able to create the team "Sample" again. But later you can go into the Agile Accelerator > Teams tab and select List Views - All, and this would also list the partial team "Sample" that was created and then this can be deleted.!
Cheers..!! :)