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: TPO657
name: 16/1986
tree-preservation-order: undefined
16/1986
tree-preservation-zone-type: group
geometry: MULTIPOLYGON (((0.663952 51.274730,0.664127 51.274653,0.664170 51.274652,0.664192 51.274665,0.664241 51.274721,0.664230 51.274747,0.664198 51.274768,0.664073 51.274813,0.663912 51.274902,0.663041 51.275331,0.662716 51.275551,0.662670 51.275545,0.662626 51.275527,0.662584 51.275498,0.662580 51.275489,0.662593 51.275458,0.663066 51.275166,0.663537 51.274921,0.663952 51.274730)))
point: POINT (0.663403 51.275083)
notes: Maidstone Borough Council Tree Preservation Order No 16 of 1986 under Section 60 of the Town and Country Planning Act 1971 Group of Trees - G3 comprising of 14 Beech
organisation
entry-date: 1986-08-13
start-date: 1986-07-19
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.