I recently changed my password and everything went fine. I'm sorry this happened to you but I notice this is your first post so at the same time I can't help but be a little suspicious of people who register on a site just to bash something/someone. Hope all is resolved soon!
It's been several yeas and was pre-kindle, but I had a similar thing happen to my account. I had not tried to change the password, but the account was frozen. They tried to get me to create a new account, but then my login for my affiliate account would have had a different email address and I would have lost all my history. They did eventually get my original account unfrozen, but it did take a few days (and a lot of calls). Similar to the person who has recently claimed to have an account closed for too many returns, my account was apparently flagged for something similar - but without ever having made any actual returns. Either a glitch at their end or someone was doing the closing by hand and missed, or someone tried to hack into the account (but I never saw any unauthorized purchase receipts) - and I had a similar problem with being "dead" to regular CS until they got it straightened out. They never did say why the problem occurred, but I've never had an issue since. However, I always back up all my purchases from them (music, books, games, whatever), as you truly are unable to access any of this is your account has a problem.
Karen
http://booksontheknob.blogspot.com/ 
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