Warning: They will shut your company account with no warning for just R300

After being a loyal customer for many years, I was shocked to discover that my company bank account was closed with no warning whatsoever. They claim to have sent an email claiming an arrear amount of R300 some odd, but I showed them that there was none received. I reside overseas and this account was invaluable to me as we used it to receive funds from large projects. I pleaded with them to reopen and I got a cold stock reply saying that if I wanted a NEW business account I should visit a branch.. Is this what they now call customer service. Pathetic service from a bank that was once the best...