Wilhelm46, sounds like you may have had a ip change on your internet provider or moved locations. The service is always going through changes, specially in the security area. Your ip may have changed, if it did, the 'unable to load channels' is the message you'd most likely get, or 'failed to get stream URL'... Fixing is easy, if you have access to your route and order #..
You can gain access easily to your route number (it's inside the stalker configuration) to reset the iptv, it's the login username and password in the configuration.. Other then that, all you need from your reseller is the order ID which he should have no problems giving you for resetting the iptv.
If you bought from a reseller who doesn't communicate well, you may want to try contacting iptv66.com's support team, and go through them when it's time to purchase again. The discount a reseller gets you isn't enough to pull your hair out each time you need something done, unless you know the person personally of course and can go beat on his door on sunday morning when the NFL games are about to start lol..
I myself purchased a reseller account just because I wanted to save some money in the long haul for myself, friends, and family members as $60 a year is better then $80... I gave them all their order#'s, donation #'s, and showed them how to update their mac and iptv reset. I also told them to contact me only after they've tried an iptv reset / mac change, as doing those things fixes 7/10 problems.