a couple months ago I decided to pay for cousins membership cause he paid me for two months in advance. I logged onto today and canceled his membership by looking up my card and all the acts that were linked to it. I'm just curious if he were to log onto his account would my card and the card info still be linked to his account to where he could reactivate his membership?
Assalamu Alaikum
It depends whether or not you ticked the "remember card" box when you did the payment.
If you didn't, and I suspect you wouldn't if you were paying for someone else, then your cousin won't be able to use your card information to make another purchase.