Imported goods damaged by DHL

In 2016 I started a company that imports clothing especially wedding dresses and evening gowns. I used DHL for my very first order, when I paid my customs fee, I was after payment put through a rigmarol of sending fotos invoices ect for the value of the product. I did this without fail. I was let know that my dress is undergoing physical inspection. Upon receipt of the dress it was rolled up into a ball and taped closed on the fabric with industrial cellotape damaging the boning and the fabric of the dress, even someones Boot print on the dress, I could not use the dress and had to reorder the item. I have queried this April of 2016 and an still waiting for this matter to be sorted. In 2017 I ordered a pair of wedding heels that was switched with a different pair of shoes before arrival and also another wedding dress was delivered to me out of the original packaging placed in a Torn up DHL bag and again crumpled up and cellotaped closed this time causing unrepairable damage to the boning inside the dress. First they agreed to a refund of $120 with was hardly close the amount in value of the products nevertheless the amount in customs I had to pay. The full cost of damage was R6003 which till now I had carried on my own, and had to flock out extra to order new items. I reported again and was informed on email that I will receive my full R6003 refund. While waiting for my refund I was informed a day before the end of the week that they have declined my refund and now will only refund me $105 as to them this is the full value of my property, which is not true because I supp**** them with my invoices. And wanted only the amount refunded of what was damaged and also what I spent on customs. I don't see why I have to pay customs on an import that was damaged beyond repair as I could no longer use this item. This complaint is dragging on for another 3months now and no effort is done to sort it out.