Where the parcel stopped

Original non-fiction-style practice text.

The station's parcel office kept a card for each package that could not be delivered. An employee wrote the attempted address on the front and a short explanation on the back. Nadiya wanted to throw away the cards once the parcels had been returned. Her supervisor asked her to compare a month's worth first.

Several cards named the same newly divided building, whose rear entrance had no number. Others recorded customers who were away whenever the morning round reached them. The office arranged clearer directions for the building and offered an afternoon collection period. The returned parcels themselves had already left the room, but the cards preserved reasons for their failed journeys.

Nadiya sorted the remaining cards into groups. She did not need to keep every piece of cardboard forever. She did need to distinguish a parcel which had been dealt with from a difficulty which would continue to affect the next one.

Give two changes the office makes after reviewing the cards.