No customer service for liquor store owners

I am a liquor store owner in the Gauteng region. I have an account with South African Breweries. The account has been opened in my personal capacity and not in the name of the business - this is an oversight on their behalf. I have been contacting them telephonically and via email to try get this corrected as it is causing havoc with my personal credit and making life very difficult for our accountant - they are just simply not interested in assisting me. There does not seem to be any kind of customer service on their side at all. I'm at a complete loss as to how to resolve this issue.