Not sure as to where my nashua account is

My Nashua account was referred to Hammond Pole attorneys ,ive been paying successfully for months now and about a month ago i noticed that my debit order didn't go off and i called them to find out as to why it happened the consultant just tells me that he cannot assist me as my Nashua account has been bought over and there's nothing he can do i must go to Mtn and go see if my account is there ,I Mean i paid successfully every month and now they cannot assist me as to tell me where my account is ? The consultant couldnt even provide me with details on where my account is i went to mtn and they advise me that my account is not there ?So now what ?