BAD service and lost parcel

My expensive parcel was delivered to the wrong address and not the address on system. I paid for my parcel and delivery, only to be told that the accounts manager at the Tygervalley branch, is contesting that I did not receive my parcel. On the system it CLEARLY shows that the parcel was dropped at a completely different address. No one is taking responsibility for this wrong action and I am being treated as if I am lying. I have been put on hold for more than half an hour on four occassions trying to sort out where my parcel is.