UPS adhere to ********ity

I ordered an item to the value of R4630, although this item is 100% duty free, I was contacted by UPS about a 20% import charge that needed to be paid, they send me an invoice to the amount of R2680.20. 20% on R4630 is R926, they added their own R1754.20 for admin, THIS IS *****! eventhough there was zero duty and taxes, they managed to add 55% additional charges - this is ********