Enter an amount (e.g. 10). A scheduled job finds customers whose birthday is today and who have not yet received this year's present, adds that amount to their digital wallet as Birthday Cashback, and sends the birthday email. With 0 the birthday email is still sent but no credit is added; with -1 the birthday routine is skipped entirely. Customers without a birth date on file are prompted on their profile to add it when a present amount above zero is configured.