They don't want to close my account.

I've paid my TFG account in full on 24/02. I've send an e-mail to request the closure of my account. I've received a reply that state that my account will be closed on 12 March. Why must I pay an account fee and interest from 25 February to 12 March? I want my account closed TODAY!!!! It is ********* to charge a client for another 12 days if they want to terminate their account today.