This can only be done by the Team owner. The Team owner is the user who has signed up for the Pro subscription and invited the others. 

Go to Your account and then Team settings. 

To remove team members or revoke the invitation, just click on the option Revoke or Remove next to their names, as in the screenshot below. 

The removed team members will lose access to the team subscription plan. 

More about Team plans: 

How to join a Team plan
​How to leave a Team plan
​How to add team members to your Iconfinder Pro plan
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