eBay has apparently closed eBay Bucks to new members and ended the 1% eBay Bucks return on daily purchases. eBay says it will still periodically offer Bonus Bucks for limited times, so the program is changing but not going away completely.
https://pages.ebay.com/rewards/faq.html#earning
Unless you activated on of those three day 5% eBay Bucks offers and made a purchase while that offer was active, none of your daily transactions would earn any eBay Bucks in the last quarter.
To contact eBay, see here:
https://community.ebay.com/t5/Selling/How-do-I-contact-Customer-Support/m-p/32016431#M1783851
