Horrible customer service and silly attitude

My parcel arrived in Johannesburg on Friday,nobody bothered to notify me about customs fees needed to clear. I had to phone them myself,only then I was notified and sent invoice to pay customs. Their online payment portal kept rejecting my way Bill number so I couldn't pay online and had to inconveniently go to pay at bank. I forwarded proof of payment to za.pop@ dhl.com,I'm now trying to follow up on why the system doesn't update. I got hold of dhl cape town they tell me I haven't paid. The whole morning from 9:00 I've been trying to clear this issue up but I keep getting passed from one person to anotherat customs department in Johannesburg , they give me attitudes, keep telling me same thing that I haven't paid of which I'm trying to explain to them but they operate robots with no time to listen and understand. They just read me what's on the system and when they're finding it hard to have patience they give me attitude or pass me around like a yoyo. This is very frustrating