Hi I am new to the frog world myself. Make sure you put some conditioned water for him to soak in, in the container. They can go a few days without food, but not water.

Also if you contact the Building Manager (your office should have details) and enquire as to where they get the plants from and then contact them. That maybe able to give you a bit of a clue. Failing that post a piccy (I just dragged and dropped mine on the thread) and the rest of us will try and help you. All the best