Print margin adjustment

I have a problem when I print. The printable area for my printer stops
about 11/16" from the bottom of the page but my system thinks it stops
1/2" from the bottom - effectively omitting the last line of each page.
This problem occurs every time I print except when I'm using an app that
has margin adjustments available.

I'm using RedHat 8, LPRng 3.8.9, my printer is a hp697c accessed via
samba.

Does anyone know if this adjustment is even possible? I'd appreciate a
nudge in the right direction, I've already searched through the lp* man
pages, and the printcap man page but nothing caught my eye.

Thx,
Bart