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: TPO327
name: 1/1969
tree-preservation-order: undefined
1/1969
tree-preservation-zone-type: group
geometry: MULTIPOLYGON (((0.531643 51.331936,0.531780 51.331941,0.531862 51.331966,0.531913 51.332005,0.531993 51.332087,0.532012 51.332150,0.532007 51.332225,0.531974 51.332301,0.531916 51.332370,0.531728 51.332468,0.531640 51.332480,0.531543 51.332466,0.531495 51.332437,0.531481 51.332406,0.531487 51.332354,0.531503 51.332307,0.531506 51.332242,0.531503 51.332200,0.531479 51.332170,0.531430 51.332137,0.531317 51.332091,0.531281 51.332067,0.531285 51.332032,0.531404 51.331966,0.531503 51.331943,0.531643 51.331936)))
point: POINT (0.531687 51.332181)
notes: County of Kent (Chatham Borough and Hollingbourne Rural District) Tree Preservation Order No.1, 1969 relating to trees and woodland at Walderslade (Rural Districts of Hollingbourne and Malling, Borough of Chatham).
organisation
entry-date: 1969-05-22
start-date: 1969-05-12
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.