R90.00 dishonour fee

I see my account has again been debited twice now with a dishonour fee of R180.00. I have requested an overdraft facility of R2000.00 as suggested by the bank in an effort to try and avoid this issue some 3 weeks back however have not had any feedback from the bank whether approved or disapproved. In this business i am in, contracting, its impossible to know when clients will make payment and therefore its impossible to manage my account without sometimes having to go into overdraft on the account. Seems the bank has no understanding of this yet they advertise with gentle music in the background how willing they are to assist small business. The way I see this behaviour is they go out of their way to destroy small business.