A few weeks after you register your domain, you'll get an email from Reclaim. It will have a link to click to confirm that you exist.
If you don't click the link, your domain will be suspended after a little while. :-(
If your domain isn't working, check to see if it has been suspended. Go to a page like this one that will let you check the registration of every domain on the web. Type in your domain. Check under the Nameservers section. If your name server is something like...
ns1.verification-hold.suspended-domain.com
... your domain is on hold.
Find the email Reclaim sent you. Click on the link. Your domain should be back up in less than an hour.
If it doesn't work, contact Reclaim technical support.