Rowdymoo

I'm setting up a villager trading hall and when I cure the zombie villagers the first time I get the discounts as expected. But when I try to cure them again to make the trade even cheaper the discount stays the same meaning i cured them the second time for nothing. I've tested in single player and I can keep curing and the trades keep getting cheaper so i'm thinking it might be an issue with my server. Does anyone have any advice for me. Thank you in advance.