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: ZZZZZWESRW936
name: Bucks County Council (Eton Rural District) Tree Preservation Order No. 7 - 1952; dated 9/10/52; made
tree-preservation-order: undefined
TPO/BCC/1952/07
tree-preservation-zone-type
geometry: MULTIPOLYGON (((-0.521527 51.496160,-0.521475 51.496202,-0.521456 51.496248,-0.521461 51.496346,-0.521482 51.496497,-0.521504 51.496579,-0.521616 51.496812,-0.521657 51.496920,-0.521697 51.496972,-0.521740 51.496996,-0.521804 51.497150,-0.522013 51.497532,-0.522149 51.497727,-0.522310 51.497917,-0.522784 51.498311,-0.522852 51.498339,-0.523638 51.498888,-0.523943 51.499082,-0.524100 51.499192,-0.524225 51.499262,-0.524433 51.499084,-0.523597 51.498585,-0.523089 51.498218,-0.523006 51.498121,-0.523061 51.498051,-0.523940 51.497362,-0.524149 51.497145,-0.524232 51.497024,-0.523650 51.497015,-0.523560 51.497000,-0.523305 51.496934,-0.523066 51.496844,-0.522926 51.496779,-0.522557 51.496591,-0.522311 51.496448,-0.522200 51.496362,-0.522164 51.496314,-0.522146 51.496249,-0.522144 51.496177,-0.521527 51.496160)))
point: POINT (-0.522776 51.497395)
notes
organisation
entry-date: 2017-07-04
start-date: 2017-07-04
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.