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: TPO442
name: 20/1987
tree-preservation-order: undefined
20/1987
tree-preservation-zone-type: woodland
geometry: MULTIPOLYGON (((0.673884 51.283699,0.673997 51.283761,0.674371 51.284126,0.674439 51.284134,0.674459 51.284154,0.674549 51.284271,0.674601 51.284426,0.674164 51.284629,0.673582 51.284821,0.673437 51.284916,0.673325 51.284922,0.673209 51.284988,0.673152 51.284552,0.673119 51.284123,0.673088 51.283981,0.673080 51.283908,0.672909 51.283491,0.672725 51.283076,0.672683 51.282928,0.672928 51.283113,0.673609 51.283550,0.673884 51.283699)))
point: POINT (0.673597 51.284099)
notes: The Maidstone Borough Council Tree Preservation Order No 20 of 1987 under Section 60 of the Town and Country Planning Act 1971 Woodlands - W9 Mixed Conifer and Deciduous trees
organisation
entry-date: 1987-07-14
start-date: 1987-07-09
end-date

Your dataset is missing the tree-preservation-order column.

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

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