To stop your membership, all you have to do is stop your recurring payments OR delete your credit card information. Your membership will stop after your next renewal date. If you want to restart your membership, you can go in and restart it at any time.
To stop payments, log into your membership page and click on "profile". You should have the option to "Stop recurring payment button" (see red box in image below). In some cases, there is no Stop button, so just delete your credit card info, and this will also cancel your membership.
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