Worst service ever!!!!

In March they swapped around 2 of my packages then claimed it was my fault. Then they lost one of my parcels sent to a customer and said I have to claim it back. After a lot of paperwork to prove that it was my parcel and how much it is worth. They said it takes 16 working days to pay out. It is now June and it still haven't been settled. The customer service is absolutely ridiculous, they don't care about their customers.