We recommend selecting the customer prior to checkout as the Happy Birthday tile will highlight on the main page if they have already joined your birthday club. Additionally this will also highlight if they currently have a valid discount:

If they do have an active discount then clicking this tile will apply the discount to the Customer's current POS order:

If the customer was added to the POS order at a later stage or you did not check the tile status prior to payment then you can add them to your birthday club after checkout via the Capture birthday tile:

A sign-up form will then pop-up. If they have already joined then you will see a message stating that "This customer is already a member of your birthday club."

If they are not a member you can invite them to join:

The form will appear using their name and email details from the order:

Please get in touch with support if you need any further assistance.