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: TPO975
name: 7/1990
tree-preservation-order: undefined
7/1990
tree-preservation-zone-type: woodland
geometry: MULTIPOLYGON (((0.667967 51.256957,0.666812 51.257316,0.666427 51.257469,0.666361 51.257476,0.666160 51.257443,0.668006 51.256809,0.667370 51.256080,0.667175 51.255810,0.667130 51.255727,0.667092 51.255631,0.666982 51.255206,0.666915 51.255072,0.666796 51.254899,0.666730 51.254822,0.666400 51.254497,0.666248 51.254327,0.666193 51.254247,0.666158 51.254166,0.666146 51.254111,0.666168 51.254162,0.666214 51.254230,0.666338 51.254364,0.666435 51.254442,0.666536 51.254444,0.666644 51.254533,0.666752 51.254634,0.667051 51.254954,0.667155 51.255092,0.667190 51.255281,0.667248 51.255475,0.667299 51.255688,0.667381 51.255693,0.667463 51.255723,0.667493 51.255747,0.667528 51.255805,0.667534 51.255827,0.667525 51.255865,0.667462 51.255952,0.667687 51.256244,0.667917 51.256495,0.668136 51.256752,0.668155 51.256766,0.668220 51.256784,0.668336 51.256779,0.668371 51.256827,0.667967 51.256957)))
point: POINT (0.667254 51.256054)
notes: The Maidstone Borough Council Tree Preservation Order No 7 of 1990 under Section 60 of the Town and Country Planning Act 1971 Woodlands - W10 mixed Deciduous consisting mainly of
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.