Standard Bank
Bank overdraft

I have one cheque account with standard bank that i am currently using. all of sudden they phoned me and tell me about another cheque account that has opened under my name and they told me that i owe R915.00 of bank over draft on the account that i don't know. what worries me is that possible to have two cheque accounts at one bank? Now my mail box is full of their messages that says as follows: settle your standard bank over draft /loan by 31/01/2013 .and i don't know anything about the other cheque acc. In october 2012 I went to Mankweng branch to complain on the matter and one of the consultant told me that they close the account and he also told me that the account will be closed in two weeks time. what worries me is that I never received any ATM card but still they keep on calling me ask me when will i come and make the payment.how can i make payment on something that you never sign any document or received any thing? please help