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: TPO367
name: 6/1983
tree-preservation-order: undefined
6/1983
tree-preservation-zone-type: group
geometry: MULTIPOLYGON (((0.613421 51.275491,0.613382 51.275494,0.613327 51.275463,0.613177 51.275278,0.613180 51.275205,0.613142 51.275163,0.613084 51.275076,0.613033 51.274940,0.613030 51.274887,0.613076 51.274811,0.613095 51.274702,0.613091 51.274685,0.613130 51.274615,0.613381 51.274598,0.613381 51.274627,0.613331 51.274713,0.613506 51.274809,0.613812 51.275136,0.613783 51.275261,0.613681 51.275362,0.613472 51.275473,0.613421 51.275491)))
point: POINT (0.61339 51.275062)
notes: Maidstone Borough Council Tree Preservation Order No 6 of 1983 as varied by the Maidstone Borough Council Tree Preservation Order No.18 of 1988 made under Section 60 of the Town and Country Planning Act 1971
organisation
entry-date: 1988-11-05
start-date: 1988-10-14
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.