Wanted to increase overdraft facility

I was a Private banking client, the service at the branch was very poor to say the least. I then asked to be transferred back to Prestige maybe the service would be better, but that was not the case. I phoned the call centre to increase my overdraft facility, it was decline because I earn commission, I must speak to my Prestige banker. I phoned and after a while a spoke to a team leader she confirmed that I can email the commission statements, she came back to me and said the amounts on my statement does not add up. I receive my commission payments weekly, on my statement it shows the total amount paid and the summary and dates paid. now they say this is not sufficient they now are looking for a letter from my accountant. Two months ago they approved me for a new home loan, new vehicle finance and previously I increased my overdraft to buy a vehicle and reduced it again. The best part of this my salary (commission) call it what you want gets paid directly into the bank account which Standard Bank can see gets run very good, I truly believe that Standard bank service is lacking and is worrying! Please come with a solution as soon as possible?