Missing Package and Rude Service

If I could give 0 stars I would. I requested an Amazon product and was given DPD as my courier. They picked it up on the 27th November and 20 minutes later, I recieve an email to say the collection was canceled as they couldn't pick up the package even though they already had it. I have spent every day since than phoning and emailing to find out what is happening. But the phone customer service people are rude and very unhelpful, going as far as ending my calls on purpose.