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: TPO398
name: 17/1986
tree-preservation-order: undefined
17/1986
tree-preservation-zone-type: area
geometry: MULTIPOLYGON (((0.640385 51.276743,0.640394 51.276753,0.640381 51.276776,0.640190 51.276996,0.639990 51.277177,0.639892 51.277167,0.639818 51.277186,0.639718 51.277141,0.639617 51.277160,0.639514 51.277127,0.639299 51.277234,0.639019 51.277301,0.638964 51.277293,0.638885 51.277242,0.638739 51.277270,0.638650 51.277296,0.638583 51.277300,0.638546 51.277285,0.638473 51.277220,0.638480 51.277185,0.638503 51.277155,0.638519 51.277147,0.638664 51.277090,0.638959 51.276994,0.639028 51.276955,0.639104 51.276899,0.639180 51.276882,0.639487 51.276576,0.639582 51.276520,0.639484 51.276465,0.639481 51.276454,0.639507 51.276419,0.639549 51.276390,0.639656 51.276343,0.639878 51.276457,0.640146 51.276569,0.640325 51.276683,0.640385 51.276743)))
point: POINT (0.639567 51.276894)
notes: Maidstone Borough Council Tree Preservation Order No 17, 1986 under Section 60 of the Town and Country Planning Act 1971 dated 19th July 1986. Confirmed 8th October 1986
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.