Expiration date issue

Hi, I’m recently change to Avast and I’m enjoying from this great antivirus. First, I installed in my notebook. Then, I installed in my desktop some days later. Now I have a problem, my notebook’s license is expiring in 4 days from now (Nov, 28). I want to know why so little time but my desktop’s license is valid till, Oct. 31, 2013. I need to fix that and I appreciate any help. Thanks in advance.

is your computer time / date / month / year correct?
if not adjust and reboot

is this avast free…did you install it as trail version?..only 30 days
you need to register to get one year

I had registered only for my desktop, it’s ok now. Thank you so much!