So I decided to purchase a 12 month subscription yesterday and managed to enjoy it for a whole day. When I try to log in today, DDI tells me that my account doesn't exist!
Way to go, Wizards! This is not a quality service. You shouldn't be ironing out problems once you've started to charge people. That's utterly unprofessional.
I don't think their CS for Digital River works on the weekends. Funny that any part of CS for an online services takes days off and not in operation, but that may be the case.
Also there was a few problems others had within the past week with expiring acounts too early or something.
WotC may not have DDI and DR timeframes set up to be compatible yet.
I think the WotC website offers a few problems in the DDI General and Technical subforums, but odds are that nothing can be done until WotC people are at work tomorrow to nail down how to fix it.
But make sure you report it to WotC as well as the subscription house CS so they can both meet on the same page to resolve the problem.