STYLETHREAD -- LET'S TALK SHOP!

Cookie dough can get old, there should be some sort of expiration date on the package. But a more likely culprit is your oven temperature gage being off. Do you have an oven thermometer? Or, the cookies might be meant to be cooked while the dough is cold, and you let them sit until they were room temp. Or, it's just a bad brand. But my guess is the oven isn't cookign at the right temp, and you can't tell because the gage is off. That's a pretty common problem.