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: TPO681
name: 16/1986
tree-preservation-order: undefined
16/1986
tree-preservation-zone-type: group
geometry: MULTIPOLYGON (((0.659896 51.286186,0.659853 51.286261,0.659811 51.286283,0.659736 51.286306,0.659605 51.286315,0.659517 51.286311,0.659430 51.286291,0.659365 51.286261,0.659303 51.286215,0.659267 51.286175,0.659257 51.286137,0.659277 51.286082,0.659299 51.286065,0.659395 51.286030,0.659470 51.286012,0.659631 51.286016,0.659785 51.286053,0.659839 51.286088,0.659884 51.286132,0.659896 51.286186)))
point: POINT (0.659579 51.286163)
notes: Maidstone Borough Council Tree Preservation Order No 16 of 1986 under Section 60 of the Town and Country Planning Act 1971 Group of Trees - G10 comprising 11 Ash
organisation
entry-date: 1986-08-13
start-date: 1986-07-19
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.