Cubase Elements 7 on my Macbook and PC

Hello, This my first post as I purchased cubase E7 today. I have a PC which I installed the software and activated with no problem. I just tried to install the mac version on my macbook and it is saying that my activation code has been used already. I was only sent one activation code for both mac and pc. Steinbergs support request process is very confusing. I just wanted to know if anyone could point me in the right direction to get my mac version activated? Thanks!

To use it on both computers, you would need to purchase a USB-eLicenser.

http://www.steinberg.net/en/shop/buy_product/sku/502009050.html