Sorry to hear about your trouble with the videos. To help you solve the problem, I first need to know which videos won't play. When you upgraded to premium membership, did you (1) find that you couldn't access the premium videos, while the non-premium videos still worked, or did you (2) suddenly lose access to all videos?
The former points to a problem with caching in your browser, where the "cookies" did not update properly to reflect your new premium status when you upgraded. (A "cookie" is a small file stored on your computer that allows our website to keep track of things like log-in and premium status). To fix this problem, you should empty your cache by way of your browser's settings menu. The process is slightly different with each browser, so do a Google search for "[your browser's name] empty cache", or let me know what browser you're using and I'll provide instructions here.
Under the second scenario, if now none of the videos play, it generally points to some sort of coincidence. There are a lot of reasons why it might appear that the videos have stopped playing, such as internet connectivity problems and so forth. But one thing I've found when people have said this is that they tried using a different computer or device. iPads and iPhones, for example, do not play the videos in their default settings. You either need to change your user preferences to Quicktime, or use our dedicated mobile website instead, http://mobile.ballroomdancers.com/
In any case, it's good to clear your cache, then restart your browser and log back in to your user account to make sure it's not a problem with cookies. When you log in, you should see that you are listed as a premium user.
Another less likely scenario, under the tech support heading of "Is It Plugged In?", is that you logged out at some point, and need to log in again. You can only access premium content when you are logged in to your user account. I know it sounds silly, but I have to check on that just to be sure.
Let me know if this has helped, or if you still need additional assistance.
Regards, Jonathan Atkinson www.ballroomdancers.com