TransferField in Purchase Invoice Header

I created a new field in Purchase Header. And all recods in this tabel has this field with some value.

I created the same field in Purchase Invoice Header

In CodeUnit 90 we have:

// Insert invoice header or credit memo header
IF Invoice THEN
IF “Document Type” IN [“Document Type”::Order,“Document Type”::Invoice] THEN BEGIN
PurchInvHeader.INIT;
PurchInvHeader.TRANSFERFIELDS(PurchHeader);

But in my Purchase Invoice the field is empty, Why?

it needs to be the same field number, name and data type in both tables for that to work.

When I need to add fields like that I usually create it in the first table, and actually copy it to the other one.