Whether they can keep charging you depends on whether they assumed your contract through the bankruptcy (I am assuming you have a contract with them, but maybe not?). When a debtor (this one being Amp'd) files bankruptcy and they reorganize, they must assume or reject all outstanding contracts. I would presume they would assume any contracts that bring in money, but if you don't want it assumed it is up to you to get it rejected in bankruptcy court. It could cost as much to deal with it in bankruptcy court as you owe, but try and at least get a copy of their chapter 11 plan and review it for how they address contracts with customers. (If you weren't sent a copy you can go to the respective court's website, sign up for a pacer account, and look it up online).
