When you purchase a subscription, it can take a couple of minutes for the subscription details to be pushed over to the search servers.
If you have bought a subscription to the Telephone Directory (which affects the 'is logged in now' search), you can access the Telephone Directory directly here.
Unfortunately, with the 'is logged in now' search, it is a case of waiting for the details to be updated. It should only take 30-60 seconds, but it could be longer during peak times.