If your card expires, the payment system (from Stripe) will attempt to automatically update your payment card details to your newly issued card. Stripe works directly with UK banks to ensure there is no interruption to your service.
If the card is not renewed, then you will need to delete the old card and add a new one. If your card expires and is not updated, you will be unable to enter or exit QwikPark car parks automatically until a valid card is added.
Instructions for payment methods can be viewed here: