Can't Update my theme!!

Hi everybody!!
Well first of all i’m new in this forum and in this big world 😉

Here is my problem:

I’ve worked before with WP but i’ve not done a lot of thing with it. Now i’ve installed WP and i’ve buy a template for my webside.
WP says that is an available update for my theme. Then i chose my template and i click to Update.
And it give me this error An error occurred while updating Nova: Update package not available.. :S
What can i do?