first of all you offend me the way you speak to me. i try to explain to everything if your logic worked that way, the quests WITH ALL ADENA REWARDS WOULD HAVE BEEN REDUCED. Also learn matters and let a gm to reply.
so its actually a bug as i said rewards CANT be reduced
also for your info i did every quest from 1-20 with adena rewards and all of them were ok. i took the rewards as the quest said. it only happened on class Quest