Disable the invitation sent:
If you have invited a team member to join you, and the member hasn't activated their account due to some issues, and furthermore they won't access it for a longer period of time than as an admin you can disable their account.
- Go to your dashboard and click on your profile.
- Scroll down the menu popped up and click on Team settings, navigate to the member's tab.
- This would have opened a directory.
- If the candidate hasn't activated their invite in zillion years.
- Their invite will be shown pending to you as being the admin.
- Then you can disable the invitation, click the button next to their profile, click Disable.
- You are done.