Just for fun I looked up how to close an Amazon account. I've never needed to and wondered how it was done. I am familiar with eBay and know it's not so easy to do & actually involves an eBay rep to close it. You don't just hit a button and you're done.
Here's what I found on Amazon.
How To Close Your Amazon Account
Right underneath the instructions to close the account are instructions on how to change your email address and remove your credit card. Apparently there are people out there who think they have to close an account when they've merely changed an email address.
So IMO this gives the OP less credibility. To close their account they'd have in all likelihood seen this message somewhere along the way trying to contact Amazon CS to close it, are you just changing your email address, then do this.
We're not getting all the facts here.