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: TPO961
name: 7/1990
tree-preservation-order: undefined
7/1990
tree-preservation-zone-type: group
geometry: MULTIPOLYGON (((0.656739 51.254845,0.656857 51.254808,0.656885 51.254807,0.656909 51.254819,0.656916 51.254835,0.656868 51.254877,0.656585 51.255024,0.656052 51.255288,0.655691 51.255477,0.655268 51.255677,0.654644 51.255988,0.654575 51.255997,0.654530 51.255977,0.654524 51.255959,0.654533 51.255946,0.654588 51.255907,0.655413 51.255511,0.655623 51.255399,0.655925 51.255259,0.656739 51.254845)))
point: POINT (0.655702 51.255413)
notes: The Maidstone Borough Council Tree Preservation Order No 7 of 1990 under Section 60 of the Town and Country Planning Act 1971 Group of Trees - G20 consisting of 37 Ash, 3 Poplar,
organisation
entry-date: 1990-10-05
start-date: 1990-10-02
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.