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: TPO806
name: 15/1986
tree-preservation-order: undefined
15/1986
tree-preservation-zone-type: area
geometry: MULTIPOLYGON (((0.682489 51.261427,0.682566 51.261454,0.683930 51.260901,0.684108 51.261095,0.683905 51.261178,0.683754 51.261258,0.682975 51.261566,0.682697 51.261690,0.682651 51.262263,0.682099 51.262414,0.682077 51.262378,0.681709 51.262533,0.681628 51.262445,0.681254 51.262233,0.681119 51.262143,0.680990 51.262024,0.680758 51.261573,0.680830 51.261497,0.681392 51.261119,0.681584 51.261215,0.681723 51.261160,0.681918 51.261102,0.682011 51.261089,0.682066 51.261109,0.682096 51.261129,0.682403 51.261369,0.682489 51.261427)))
point: POINT (0.682049 51.2617)
notes: Maidstone Borough Council Tree Preservation Order No 15, 1986 under Section 60 of the Town and Country Planning Act 1971 dated 18th July 1986. Confirmed 8th October 1986
organisation
entry-date: 1986-08-13
start-date: 1986-10-08
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.