Sadly Travels, this happens almost everywhere. In this village, the local F'book last month was lit up with "where is my post?" comments, assorted mail delayed for up to 2 weeks. It turned out that THE postman (just the one!) was ill, and there were no other staff. If they'd contacted the Parish Council, a set of sub 'posties' could quickly have been assembled, like the 'need any help' band of volunteers in Lockdown.
People anticipating Xmas cards rolling up in time for Easter (but which year?!) might like to try an 'E-Card', lots of firms but we use jacquielawson.com who have a very good range.
Courier forms (for parcels) get a barrage of complaints too, almost every day that local F'book has a picture of the bottom of a front door, with a parcel that was 'delivered' -- and the would-be recipient is asking "whose door is this, my parcel isn't with me?". And that's because drivers have to deliver a million a day (?!) and neither they nor the firm cares much exactly where they went, just glad they're not in the depot!