CUSTOMER RESPONSIBLE FOR DAMAGE IN TRANSIT

I ordered a motorcycle screen from DMD in Jhb and on arriving here there was no brackets in the parcel. So they said I must send it back which I did with Skynet couriers on DMD's account. DMD notified me that the screen was damaged when they received it there. So they said I must pay for the damaged screen which was obviously damaged in transit. How come that a client can be held responsible for damages caused by a transport company? That is definitely not right. I would like to here from Skynet in this regard, because it seems that they are not very high rated what anyway concerning their service.