Selling Books on Amazon

Ok so I go on amazon alot cuz thats where I buy most of my books cheap or whatever else i need... So I wanted 2 sell some books and chegg wouldnt buy them n wanted me to donate them instead. I'm like ok I really need to sell those books so I try to sell them on amazon and end up losing money lol...I can't do stockes or be n accountant. Idk how that happened i think there was some kind of miscommunication somewhere i jus dont no where lol... From now on its chegg or selling at skool I can afford paying 4 books i already bought...fyi amazon is ur enemy not ur friend!!!