Tree preservation zone

There is a problem

tree-preservation-order column must match the reference field in the tree preservation order dataset

reference: TPO405.G1
name: Situated in the communal space to the front of Gambier Terrace.
tree-preservation-order: undefined
TPO405
tree-preservation-zone-type: group
geometry: MULTIPOLYGON (((-2.971175 53.398484,-2.971228 53.398518,-2.971257 53.398504,-2.971153 53.396825,-2.970973 53.396921,-2.970967 53.396948,-2.970985 53.397117,-2.971006 53.397144,-2.971006 53.397181,-2.970989 53.397199,-2.971002 53.397379,-2.971031 53.397425,-2.971008 53.397461,-2.971024 53.397636,-2.971069 53.397671,-2.971085 53.397695,-2.971073 53.397718,-2.971034 53.397754,-2.971038 53.397798,-2.971084 53.397832,-2.971103 53.397870,-2.971085 53.397909,-2.971032 53.397932,-2.971037 53.398023,-2.971087 53.398046,-2.971108 53.398093,-2.971093 53.398131,-2.971047 53.398156,-2.971068 53.398349,-2.971058 53.398350,-2.971074 53.398389,-2.971132 53.398452,-2.971175 53.398484)))
point: POINT (-2.971119 53.397657)
notes: 6 London Plane, 12 Holly, 1 Lime, 3 Ash, 14 Sycamore, 1 Elm & 2 Maple
organisation
entry-date: 2012-04-20
start-date: 2012-06-15
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.