A rather more minor issue with DPD which does highlight an issue with their computer system.
I ordered two items from different suppliers - a pedal from G4M and some rechargeable batteries from Ikea, both of them for drop-off at the local post office. I got notifications that both were in transit, then got a notification that the pedal was ready for collection, with a QR code. Went to the post office, and the lady on the desk went looking for my parcel. She returned with the Ikea one. I told her that there should be another one as well, and she had another hunt and found the G4M parcel. She gave me that but wouldn't hand over the Ikea one as it wasn't showing on the system. Then the next day I saw that the parcel was now showing as collected. I've been back to the post office - the week that I'd been in to collect the stuff, the staff were agency staff, and the full-time lady never managed to find the parcel. Ikea have refunded me (for the batteries, not the postage) and I've bought the same thing from Ebay, delivered to my house.
I've raised this as an issue with DPD - the G4M parcel racking history shows as in transit, then ready for collection, then collected. The Ikea one just shows as in transit, then collected. I assume that the QR code is generated at the point where the status changes to "ready for collection" so it would appear that an item can be collected without a QR code, which makes a mockery of security.