I didn't have a problem, but the genie and my sim was best friends at that point. The option was available to click on just like any other wish. Once I clicked on the free the genie wish I had several pop-ups come up that had to be completed to "weaken" the magic binding the genie to the lamp. You end up needing to freeze the lamp, then bake it in the oven, and then finally taking it on a trip through the catacombs. Once you do those three things you will again summon the genie from the lamp and it will then join your family as a playable sim.