INADEQUATE CUSTOMER SERVICE ACTIVITY AND PROCESS

I purchased sports clothing from the UK, and payment included a courier of their choice ... in this case DHL. The clothing has arrived with DHL Express South Africa, and DHL forwarded an Import Duty and Vat invoice which is incorrect. Tariffs app**** under General, which should have been EU/UK, and so are substantially higher. Been in contact with 6 people now at DHL (you get a new contact as the email trail grows), including a Customer Care Executive, and despite many document requests, all supp****, my simple request to correct the import tariffs simply falls on deaf ears ... I neither chose nor paid directly the courier (paid for by the the supplier who paid the courier, hence the parcel is in South Africa), and yet this seems to be DHL's main concern. Even the supplier wrote an email saying this is the first time they've experienced a payment issue. Please ... I simply want my goods and to pay the correct import tariff.