To remove the member, see my Forum Leader Tip:
Somewhere in there in mentions that for the free version, you need to in the same team as the user you want to remove, so temporarily add them to a team you’re in, then you can first remove them, then are offered to deprovision.
Regarding removing “First Team” if you can’t get access to the team you’ll need to contact Support: To create a support ticket, go to www.asana.com/support (make sure you are logged in to Asana) > click the chat icon at the bottom right > type “speak to an agent” > click “Yes” > click “Something Else” > click “Create a support ticket.”
Thanks,
Larry