Unable to increase production of second city

Just started playing civ5.. I founded a second city and it is stuck on a production of 2, in spite of the fact that I improved on some tiles and added quarry and mine to them. When I hover over those tiles it says +2 on both of them (for a total of 4), and adding in the +1 production from another tile plus the +1 from the tile on city itself should give me a total production of 6... So what's going on? It makes this second city completely useless with such a low production. Any help is much appreciated.

Click on Citizen Management in the upper right and tell it to specifically work those tiles.

Open "Citizen Management" and see if you have someone assigned to those hexes.

Edit: Ha, too slow!

You have to Reassign Citizens to work Tiles that you have Improved. Alternatively, you can select Production Focus and the Client will prioritize Production Tiles automatically in that City.