hi guys, 

i try to upgrade my troops but do not succeed.. when i want to upgrade my Crossbowmen e.g. i allways read that i do not have enough strategy ressources.. but when i check my ressources i should have 1 iron.. does anybody know what to do?

thx

The crossbowmen upgrade to Arquebusiers, which require 1 Iron and 1 Saltpetre. Also under the card of the new unit you should see a resource in red, that is the one missing.