When setting up a team, only the account owner and designated administrators have the ability to add or remove team members through the team page.
Removing a User
Through your team page, select the ··· menu next to the team member's name and choose "Remove from team" from the drop-down menu.
A pop-up modal will appear for you to confirm that you really want to remove the team member from your team. Note: Removing a team user from the team will transfer any canvases they've owned or created to their individual account.
Make sure to have their canvases transferred to someone else on the team. This can be done by either the account owner, an admin, or the canvas owner.
Once the canvas transfers are finished, that team member can be removed.
That's it! You can now add or remove users through your team page.