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: TPO394
name: 6/1983
tree-preservation-order: undefined
6/1983
tree-preservation-zone-type: woodland
geometry: MULTIPOLYGON (((0.610582 51.274736,0.610594 51.274756,0.610615 51.274875,0.610644 51.274932,0.610835 51.275162,0.610846 51.275189,0.610858 51.275272,0.610913 51.275357,0.610914 51.275419,0.610980 51.275489,0.611010 51.275575,0.611073 51.275628,0.611179 51.275836,0.611741 51.275676,0.612526 51.276681,0.612615 51.276774,0.612573 51.276785,0.612544 51.276804,0.612633 51.276890,0.612653 51.276891,0.612826 51.277099,0.612385 51.277189,0.612186 51.277207,0.611939 51.277242,0.611639 51.277291,0.611427 51.277339,0.611398 51.277337,0.611276 51.277274,0.610864 51.277241,0.610818 51.277244,0.610640 51.277283,0.608787 51.275564,0.609293 51.275416,0.609492 51.275334,0.609600 51.275304,0.609756 51.275226,0.609988 51.275149,0.610131 51.275062,0.610417 51.274836,0.610538 51.274774,0.610582 51.274736)))
point: POINT (0.610822 51.276224)
notes: Maidstone Borough Council Tree Preservation Order No 6 of 1983 as varied by the Maidstone Borough Council Tree Preservation Order No.18 of 1988 made under Section 60 of the Town and Country Planning Act 1971
organisation
entry-date: 1988-11-05
start-date: 1988-10-14
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.