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: TPO771
name: 6/1976
tree-preservation-order: undefined
6/1976
tree-preservation-zone-type: woodland
geometry: MULTIPOLYGON (((0.595491 51.315823,0.595202 51.315951,0.594902 51.316104,0.594871 51.316078,0.594745 51.316010,0.594630 51.315922,0.594515 51.315851,0.594253 51.315730,0.594073 51.315628,0.593792 51.315492,0.593566 51.315372,0.593045 51.314974,0.593109 51.314907,0.593152 51.314874,0.593342 51.314762,0.593485 51.314702,0.593651 51.314654,0.594304 51.314507,0.594568 51.314437,0.594763 51.314625,0.595249 51.315246,0.595338 51.315375,0.595401 51.315487,0.596002 51.315572,0.596252 51.315883,0.596433 51.316078,0.596656 51.316274,0.596847 51.316418,0.597089 51.316680,0.597184 51.316735,0.597403 51.316835,0.597480 51.316879,0.597638 51.317065,0.598254 51.317658,0.598853 51.318217,0.598675 51.318515,0.598396 51.318230,0.598072 51.317943,0.597914 51.317771,0.597208 51.317146,0.597137 51.317037,0.596796 51.316842,0.596538 51.316729,0.595542 51.315813,0.595491 51.315823)))
point: POINT (0.595512 51.315907)
notes: Maidstone Borough Council Tree Preservation Order No. 6 of 1976 under Section 60 of the Town and Country Planning Act 1971. Woodlands - W2 Comprising Yew, Hazel, Oak
organisation
entry-date: 1976-06-11
start-date: 1976-06-11
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.