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: ZZZZDTESXE971
name: The Chiltern District Council (Land at 57 Sheepcote Dell Road, Holmer Green) Tree Preservation Order
tree-preservation-order: undefined
TPO/1995/005
tree-preservation-zone-type
geometry: MULTIPOLYGON (((-0.685936 51.666773,-0.685932 51.666780,-0.685931 51.666788,-0.685932 51.666794,-0.685941 51.666806,-0.685949 51.666811,-0.685967 51.666817,-0.685993 51.666816,-0.686010 51.666809,-0.686025 51.666798,-0.686037 51.666783,-0.686050 51.666775,-0.686062 51.666765,-0.686081 51.666742,-0.686082 51.666730,-0.686080 51.666724,-0.686075 51.666717,-0.686067 51.666711,-0.686058 51.666707,-0.686041 51.666703,-0.686018 51.666705,-0.685995 51.666715,-0.685986 51.666721,-0.685977 51.666732,-0.685962 51.666744,-0.685949 51.666757,-0.685936 51.666773)))
point: POINT (-0.686006 51.66676)
notes
entry-date: 2010-02-18
start-date: 2010-02-18
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.