Add a new card from the invoice preview screen
You can also add a new card when in the "Preview & send invoice" screen. Click on the green "Pay Now" button and you can enter their card details and choose to "Store" for future invoices.
To update/change the stored credit cards for a client please follow the below steps:
1. Search for client under "Contacts" section
2. Click on "View Details" on the right for the contact
3. On the right under "Payment cards" you can choose to "Delete" an existing card or "Add new card"
4. Once completed you can then use the card in the "Preview & send invoice" screen
Prefer your clients to enter their credit card details?
Checkout out this self service workaround guide on how to do this.