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: TPO967
name: 7/1990
tree-preservation-order: undefined
7/1990
tree-preservation-zone-type: group
geometry: MULTIPOLYGON (((0.657132 51.254848,0.657164 51.254848,0.657222 51.254879,0.657482 51.255260,0.657797 51.255682,0.658017 51.255994,0.658253 51.256290,0.658269 51.256324,0.658265 51.256349,0.658249 51.256374,0.658187 51.256399,0.658119 51.256389,0.658067 51.256363,0.657223 51.255223,0.657010 51.254925,0.657015 51.254901,0.657028 51.254884,0.657060 51.254866,0.657132 51.254848)))
point: POINT (0.657634 51.255618)
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 - G21 consisting of 31 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.