Non delivery by DHL "said to be EXPRESS"

I bought a parcel on line for the value of R2 655.00 from an offs**** supplier for delivery by DHL on 08 March 2017. I received an invoice ofR2 613.90 from DHL for custom duties for a parcel weighing 0.50kg. After disputing the invoice for months, the invoice was revised to R1 164.00 on 23 May 2017. On 22 June 2017 I sent proof of payment to Charles Mbamba, the cosultant I was liaising with. Sadly, I've never heard from DHL ever since and have never received my parcel. Charles has never responded to any of my follow up emails. Other consultants dealt with were Ms Seline Muwkevho and Mr Lucky Siphiwe who I've also never heard from again. In the end I regrettably lost R3 819.00. Very disappointed.