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: TPO24
name: 7/1996
tree-preservation-order: undefined
7/1996
tree-preservation-zone-type: group
geometry: MULTIPOLYGON (((0.601525 51.265616,0.601372 51.265596,0.601238 51.265563,0.601078 51.265566,0.600974 51.265548,0.600913 51.265495,0.600936 51.265451,0.601083 51.265440,0.601150 51.265456,0.601339 51.265457,0.601430 51.265466,0.601498 51.265490,0.601614 51.265516,0.601776 51.265541,0.601954 51.265555,0.602048 51.265553,0.602104 51.265593,0.602143 51.265640,0.602108 51.265665,0.602044 51.265687,0.601913 51.265692,0.601858 51.265683,0.601707 51.265627,0.601525 51.265616)))
point: POINT (0.601536 51.265559)
notes: The Maidstone Borough Council Tree Preservation Order No 7 of 1996 under Section 198 of the Town and Country Planning Act 1990 Group of Trees - G1 - consisting of 2 Birch, 1 Field
organisation
entry-date: 1996-03-08
start-date: 1996-03-08
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.