Sneaky. Stupid. Desperate

I closed and settled my account in october 2016.i have received 2 calls telling me that my account was over due. After 2 calls and a lot of telling them to open their eyes and look on theirs system that i no longer had a account. I was only told o sorry the system kept billing your standard bank account that has been non active in a year!!!!! Stupid people who don't know how to do their jobs!!!!!