You can contact Customer Service regarding all account matters via the link under Useful Links at the top of this page.
Likewise Technical Support for all product support matters.
However in answer to your activation question. I gather form your post that you've already activated the software once before, am I correct?
If so, all you need to do is go to your account and reinstall from there: see 'Downloads' under Useful Links and look for 'My Account' over at the the right side.