Hi @Anonymous User
Have you get any scheduled payments due to nowtv before your new replacement card arrives?
If not then you should be able to update your new card details by going to My Account > Personal Details on here.
However, if it was me i would jump over to live chat or drop them a message from the link below to inform them that you lost your current bank card and waiting for a replacement new card.
Link here to live chat.
https://help.nowtv.com/contact-us/managing-my-devices
