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: TPO187
name: 21/1987
tree-preservation-order: undefined
21/1987
tree-preservation-zone-type: woodland
geometry: MULTIPOLYGON (((0.676874 51.269812,0.676562 51.269804,0.676267 51.269827,0.675505 51.269943,0.674739 51.270088,0.674402 51.270109,0.674112 51.270156,0.673850 51.269552,0.674816 51.269374,0.674275 51.268203,0.674658 51.268154,0.674969 51.268829,0.675400 51.269799,0.676643 51.269683,0.676877 51.269689,0.676905 51.269700,0.676893 51.269715,0.676895 51.269749,0.676883 51.269812,0.676874 51.269812)))
point: POINT (0.674856 51.269456)
notes: The Maidstone Borough Council Tree Preservation Order No 21 of 1987 under Section 60 of the Town and Country Planning Act 1971 Woodlands - W6 Mixed Conifer & Deciduous trees
organisation
entry-date: 1987-07-31
start-date: 1987-07-30
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.