How to use the merchant?

[Azertyuii]

Hello.

I am playing the new cities and knight expansion.
I just played a merchant next to one of my settlement and was trying to use the 2:1 ability but I couldn't find how to do it.

When I open the maritime trade, the 2:1 ratio is displayed but everytime I click one of my resources it automatically select 4.
I actually wants to trade 2 so I would be fine with doing 4:2 but I can't accept this trade when I select these resources.

The merchant has been played on the same turn if that makes a difference (nothing written on the card about having to wait a turn though)

Any idea of what I am doing wrong? Might that be a bug? I checked the report list but it doesn't looks like there is a similar issue in there.

Thanks

[euklid314]

I believe you interpreted the trading function the wrong way around. If you are putting the the trader on, say, an ore hex then you have a "virtual" ore haven. You can now trade ore 2:1 - instantly after you placed the merchant, i.e., even in the same move.

But that does NOT mean you can trade 2 same ressources and get 1 ore but it means you can trade 2 ore and get something else! If you open maritime trade and click on ore it will only choose 2 ore instead of 4 ore. If you click on another ressource, say wood, it will choose 4 wood since you have no 2:1 wood trading.

I often see players put their merchant on their least productive hex instead of their most productive hex.

[Azertyuii]

I indeed understood the trading function the wrong way.

Thank you for clarifying things.

[VladUkraine]

Thank you Euklid for explanation!
Where I could read all the rules about Cities and Knights?.
Playing Catan many years, but have no clue, how to play latest version.