Tree preservation zone

There is a problem

1000 entries with tree-preservation-order field must match the reference field in the tree preservation order dataset

reference: ZZZZDVESXE704
name: The Bucks County Council (Amersham Rural District) Tree Preservation Order No 6 - 1952 Confirmed by
tree-preservation-order: undefined
TPO/1952/006
tree-preservation-zone-type
geometry: MULTIPOLYGON (((-0.593033 51.608489,-0.593043 51.608504,-0.593079 51.608517,-0.593209 51.608532,-0.593585 51.608553,-0.593880 51.608578,-0.594126 51.608613,-0.594387 51.608643,-0.594533 51.608670,-0.594623 51.608680,-0.594655 51.608680,-0.594687 51.608674,-0.594713 51.608652,-0.594732 51.608627,-0.594732 51.608605,-0.594714 51.608588,-0.594686 51.608574,-0.594636 51.608567,-0.594510 51.608561,-0.594407 51.608553,-0.594271 51.608531,-0.594097 51.608507,-0.593965 51.608483,-0.593658 51.608450,-0.593290 51.608426,-0.593078 51.608409,-0.593049 51.608415,-0.593038 51.608435,-0.593033 51.608462,-0.593033 51.608489)))
point: POINT (-0.593866 51.608536)
notes
entry-date: 2010-02-18
start-date: 2010-02-18
end-date

Your data is missing a tree-preservation-order.

The Tree preservation zone guidance explains how to fix the issue:

The reference for the tree preservation order that covers this zone.