The Villager trade system has broken and villager cannot level-up the market, sometime exp from trade not apear and if village have huge amount emerald trade they will not take the emerald and give the item for FREE !!!!😉
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Comments 2
As this are two issues; resolving his as duplicate of MC-141887 and I will make a report about the 'free item' bug (thats more detailed).
I have got problem with trade level too. My villager's trade rank reset to lowest level after reload game