How to delete your RingCentral App Account
• Contact one of your company's administrators if you would like to delete your account but other people from your company will continue to use the RingCentral App, and they can remove you. Click Contacts at the bottom of the Left Pane, then select Admins from the Show list at the top of the page to see the list of administrators.
• If you would like to remove your entire company from the RingCentral App, and your company has a subscription to one of RingCentral App's paid plans you’ll need to contact customer support to have your company removed.
• If you're an Admin, click Contacts at the bottom of the Left pane and click on the More (ellipsis) button next to the person you want to remove. You'll see an option to deactivate them there.
RingCentral App - Overview