Citibank Bank Account Or Service Complaint

Citibank Bank account or service department,

Other bank product/service Account opening, closing, or management New York

I was a CITI BANK customer several years ago. I have closed my checking, saving and debit accts. Recently, I have been receiving notices that these accts are below minimum balance I had set for them. I have complained several times but I still get theses e-mail notifications several times a week. I maintain my mortgage with Citi, but they say they have NO control over them. I have complained to Citi Bank it self and they say they ca n't locate thr origin of these messages. Besides being a pest I am worried that at some point they will try to get maintenance charges for theses accounts.