Hi @Claireabell
Just to reiterate what @Lurch said here - the knowledgebase is a great place to start and often provides step-by-step instructions on how to take care of situations like this (with screenshots).
The exact guide for credit cards can be found in the link @QFBeth shared above, but for convenience, you can find it here: Managing credit cards in QuickFile.
Please do let us know if you need help - it’s why we’re here, as well as the rest of the community. But the guide is definitely a good place to start.