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: TPO216
name: 19/1987
tree-preservation-order: undefined
19/1987
tree-preservation-zone-type: group
geometry: MULTIPOLYGON (((0.656258 51.274855,0.656373 51.274898,0.656490 51.274992,0.656588 51.275109,0.656913 51.275349,0.657008 51.275360,0.657222 51.275246,0.657445 51.275148,0.657516 51.275101,0.657570 51.275082,0.657653 51.275117,0.657668 51.275200,0.657607 51.275266,0.657382 51.275414,0.657235 51.275477,0.657151 51.275533,0.656949 51.275618,0.656900 51.275614,0.656847 51.275585,0.656695 51.275462,0.656578 51.275339,0.656331 51.275167,0.656236 51.275065,0.656176 51.274982,0.656154 51.274933,0.656179 51.274891,0.656258 51.274855)))
point: POINT (0.656889 51.275272)
notes: The Maidstone Borough Council Tree Preservation Order No 19 of 1987 under Section 60 of the Town and Country Planning Act 1971 Group of Trees - G12 Consisting of 21 Field Maple,
organisation
entry-date: 1987-08-11
start-date: 1987-08-05
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.