I can't install the newest pack. Help!

Hi, this is my first time posting here.

I just bought the newest Business and Hobbies Expansion pack. The thing is, I can't download it. It doesn't show up in my Manage add-ons nor in the Download Queue. When I entered the game, it recognized that the pack is there, but the new world is grayed out and says something along the lines of "the pack isn't installed yet". What do I do? Yes I checked that I actually bought the pack. I have the bill and I checked on my purchases that I did.  Does anyone know why this happens and how do I install it? I haven't had this trouble with previous packs.