CANCEL MY ACCOUNT AND STOP MESSAGING ME!

I have not used my account from 2012 for my salary, the only reason i kept the account was because my credit card installments were coming off the account. When i settled my credit card in July this year, i asked the person from the call centre to cancel my savings account, they said they could not and i need to go to a branch. i work monday to saturday and do not have the opportunity or time to go. I have not used the account since and keep getting messages on my phone regarding outstanding amount and fees? How can that be when ii am not using the account? Please cancel my account as it is no use to me. You can see the account is not in use yet you are still charging me fees?!