In your E-junkie Seller Admin > Cart Discount Settings, you have a discount named "Seminar" for 50% off the Item Total, which has no Discount Code(s) entered, so that discount is applied automatically to every order that meets the thresholds of Min. Item Total = 1 and Min. Order Total = 0.00, without requiring the buyer to enter a code. You have also set this discount's Max. Use Count = 2, so it would only work for 2 orders and then expire.
This help page explains more about discount settings: