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: ZZZZZWESRW918
name: Eton R.D.C. Tree Preservation Order (No.2) 1974; made under Ss.60 and 61 of the Town and Country Pla
tree-preservation-order: undefined
TPO/ER/1974/02
tree-preservation-zone-type
geometry: MULTIPOLYGON (((-0.620240 51.552349,-0.620333 51.552259,-0.620375 51.552221,-0.620548 51.552072,-0.620625 51.552010,-0.620547 51.551972,-0.620496 51.551942,-0.620452 51.551921,-0.620403 51.551900,-0.620313 51.551873,-0.620141 51.551844,-0.620143 51.551763,-0.620193 51.551495,-0.620089 51.551478,-0.619817 51.551420,-0.619388 51.551484,-0.619274 51.551513,-0.619290 51.551527,-0.619311 51.551535,-0.619331 51.551547,-0.619351 51.551565,-0.619377 51.551593,-0.619409 51.551631,-0.619470 51.551712,-0.619491 51.551737,-0.619511 51.551768,-0.619512 51.551784,-0.619508 51.551789,-0.619494 51.551796,-0.619462 51.551806,-0.619425 51.551820,-0.619399 51.551835,-0.619364 51.551861,-0.619334 51.551881,-0.619316 51.551891,-0.619242 51.551916,-0.619206 51.551925,-0.619175 51.551936,-0.619127 51.551964,-0.619185 51.551989,-0.619191 51.551994,-0.619198 51.551997,-0.619362 51.552019,-0.619626 51.552060,-0.619685 51.552083,-0.619795 51.552098,-0.619759 51.552225,-0.620240 51.552349)))
point: POINT (-0.619894 51.551871)
notes
entry-date: 2017-07-04
start-date: 2017-07-04
end-date

Your data is missing a tree-preservation-order.

The Tree preservation zone guidance explains how to fix the issue:

The reference for the tree preservation order that covers this zone.