User defined reporting - "In Reference to" in Slips

SOLVED

Hello all,

I am creating user defined reports in Timeslips 2017 (perpetual license).

I have been merrily creating Client reports which include the "in reference to" field from the client record. Not a problem

I have tried creating User Defined Slip and Billing reports using the same "in reference to" field from the client record and it comes back blank. I wouldn't have thought Sage would have put it there unless it was able to be used. Other fields from the client record are coming up fine. This one, not so much.

Any ideas? Is this happening for anyone else?