Thank you for providing the extra details.
In that case, I would recommend what pdurrant suggested in his post - sending the CIS an email with a list of your accounts, your reason for closing the previous account, and also your questions/concerns about your seller account. If nothing else, they should address your concerns about your customers, and that may force them to look more closely at the account and possibly resolve this.
If that goes nowhere, you may need to look at the Amazon terms - both the regular account terms and the Seller agreement - and see what your options are in regard to disputes and resolution.