As mentioned in this article, once you've activated your card you will not be able to change the number of stamps on it.
This is because of technical reasons, and also to ensure that your customers have the best experience. For example, we wouldn't want them to be shocked if they notice the number of stamps on their card has suddenly changed.
If you do find that you want to change the number of stamps on your card, here's what you could do:
Create a new card with the new number of stamps
For existing customers, manually transfer stamps from their old card to their new card. You should already know who's signed up for your previous card by looking at the Customers table.
Manually sign them up for the new card, add the appropriate number of stamps, and then send them a link to their new card.
Key Points to Remember:
Be sure to let your customers know that the old card will no longer be supported and that they will need to install a new one.
Ensure staff know of the change as well so if customers come in with their old cards, staff can help transition customers to the new card.
If you already have posters printed, you will need to get them reprinted with your new digital stamp card URL / QR code.