To change your payment information your subscription must be unsubscribed and expired.
When the subscription is expired you can sign up for the subscription again. Here you have the possibility to enter your new payment information.
If you want to renew your subscription you start by signing in with your e-mail address and your password. Hereafter, click on the 3 horizontal bars in the top right corner and select “Buy premium”.
Then you need to choose which subscription you want. Afterwards, you will be forwarded to the payment page where you can enter your new payment information.