We don't have such a feature in Seller Admin at present, but we can add that suggestion to the wishlist for consideration as a possible new feature in the future.
Meanwhile, our Development team may be able to delete used codes (where Use Count = Max. Use Count) for you manually. To confirm your identity and attend to this request, please email our Support team your E-junkie account password, or your original activation code would suffice if you still have your original "Account information" email from us:
https://www.e-junkie.com/ej/contact.php
