If you do not want to automatically renew your membership or you have problems adding a credit card (like mine), you can turn off automatic renewal at the bottom of the membership area. This will create a new button to renew your membership manually. I had to do this a couple of times before the button appeared, and it worked not in Safari, but only in Chrome ...
When you manually renew your membership, you can enter a new credit card, which will be used only for this payment. This only worked in Chrome, NOT in Safari.
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