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: TPO420
name: 20/1987
tree-preservation-order: undefined
20/1987
tree-preservation-zone-type: group
geometry: MULTIPOLYGON (((0.670053 51.278153,0.670080 51.278168,0.670079 51.278244,0.669921 51.278315,0.669547 51.278415,0.668854 51.278497,0.667981 51.278554,0.667322 51.278628,0.667018 51.278701,0.666608 51.278827,0.666512 51.278830,0.666463 51.278803,0.666431 51.278772,0.666452 51.278725,0.666549 51.278677,0.667050 51.278546,0.667318 51.278488,0.667594 51.278447,0.669007 51.278371,0.669260 51.278324,0.669943 51.278157,0.670053 51.278153)))
point: POINT (0.668231 51.278484)
notes: The Maidstone Borough Council Tree Preservation Order No 20 of 1987 under Section 60 of the Town and Country Planning Act 1971 Group of Trees - G4 comprising 4 Ash, 3 Oak,
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.