Bug about trading with the Cartographers

When I wanted to trade with the cartographer to get a map, I found that if I click on the list on the left side to fill the emeralds and compasses into the trading grid, I cannot get a map. But if we manually put these items into the grid, I can get the map as usuall. The situation only happens on trading maps with the Cartographer.

(I'm from China so I'm not good at grammar. Hope you can know what I mean. )