… The problem is that the Post Office and Royal Mail are separate entities, whose daft idea was that?
Exactly so, especially since separation the two businesses don’t seem to get on. Competition isn’t always good for the customer!
Normally, I understand the drill for Express 48 is to connect to Royal Mail online, who take payment and issue the necessary documentation there and then. Then they either collect the parcel from your home address, or you leave it with a Post Office. The Post Office is just a collection point, not part of the tracking and payment process.
I guess if a parcel is taken direct to a Post Office, they do the Royal Mail admin behind the counter, and might get it wrong. One possibility is that that the Post Office use other carriers, not just Royal Mail. It’s possible Alastair has been given an EVRI or DPD tracking number, or that the Post Office gave a Royal Mail parcel to the wrong carrier, who is baffled because they don’t understand the labelling! Possibly the parcel is wending it’s way through some complicated inter-carrier error system. I believe they all send lost parcels to their failed to deliver handling point, Amazon’s is in Aberdeen. There, detective work might identify the sender, or who should be handling it, but much depends on what went wrong.
Try entering the number into the EVRI and DPD tracking system. With luck they might recognise it.
A Royal Mail reference number will be between 9 and 27 characters long. EVRI and DPD references are between 10 and 16 characters.
Dave