The settlers, threat from the north, ipod touch?

here is the problem. i have all the building necessary. i have plenty of food, water, wood, mines, but there comes to a part where they stop producing. what i mean if i want more axes or hammer it does not get done. i have build alot of houses but it does not work. i want more soliders but went i click the on nothing happens. i can see that i can click for how many i want but the workers do not do any thing. it is like a strike or some thing. am i missing something here.