How to show an empty field if the result is an Error: Field not Found?

Hi All,

I added a custom transaction line (non-stored) field to Sales Order Lines that shows the {actualshipdate}. The issue is that when we first enter an order, it shows an error (see screenshot).

Once the order is approved, this error goes away. I would like to show nothing instead of the error.

I am trying to figure out how to find the main line (header) status of the order. ie:

case when {status} = 'Pending Approval' then '' else {actualshipdate} end

This then has an error "Error: Field 'status' not found."

Any help on how to reference the parent/header status field or simply showing blank instead of an error would be much appreciated!