FNB extremely unprofessional and inconsiderate

Always been with FNB, N1 city, Goodwood. I easily receive deduction SMSes in this account. I had about -R750 in my account, 2 weeks ago my internet banking said R0. My new salary was transferred in this account. 3 days ago, I went to the bank and was told it was closed and I received no notification, no phone call, SMS, or even email. Spoke to an consultant, her reply \we don't notify the customer". I explained to her if my account says R0 then I owe nothing. My salary was reversed or sent back and no indication about this. To me"