You can easily add a new payment method from the app. Keep in mind that when you add a new one, it will be set as the default payment method. To do this, tap the motorcycle icon in the bottom menu and then select "Subscription."
If you already have a payment method set up in Apple Pay or Google Pay, you won’t need to enter it manually. Click the button that appears below the "Add payment method" button, and it will be completed automatically.