been reporting ***** without assistance

Dear fnb I have been reporting unauthorised debit orders on my account and I am not getting any help from you. When I called your call centree the gentleman I spoke to couldn't help me because I didn't have my cards but had my I'd number. I then saw missed calles from fnb on friday the 27th and returned ur call and only to find out that all your lines are busy. How do u urselgnise that the debit order is unauthorised and still process it anyway?