Christmas gift missing parcel on order

We ordered a parcel on the 06/12/2021, 3 items ordered on order #***9 went to collect on the 18th only received two items collection office cannot find the other item on the order my fiancé was told to sign for all 3 and that they will call him as soon as they find the parcel. We went to collection office again this morning still they can not find it. this is very disappointing as this is a Christmas gift we need before the 22 December. how do you just loose a parcel scanned into your system.