Every team and a team member must have an account. Accounts from the old system were transformed.
First person who creates a new team account has its personal account automatically created and becomes the Team Captain. Only Team Captain can manage team's account (edit it, register for events, accept team members, pass captain role to someone else).
Regular Team Member must create an account, so the Team Captain can assign her/him to event. Affiliation of a new Team Member is confirmed by Team Captain in the account.
Please check if your team hasn't been created before you do so. Following teams were registered.