Can I change payment method?

Yes.

Log in to Abra Store. Click on your name at the top right and then "My account". From here you can manage your payment methods, and e.g. change cards.

NB - if you already have an active subscription, you cannot delete the card you have as a payment method, then you must first add a new card, and then select this as the payment method. You can then remove the other/old card.