In order to make purchases, such as memberships, credit packs or products, you'll need to add a credit or debit card to your account. This is also required if you have a recurring membership, so that you are able to make your regular payments and keep your memberships active.
Add a Payment Method to Your Account
To add a payment method to your account in the app:
Log into your account
Tap on Profile (in the bottom right) > Payment Methods > Add New Card