Use Alt-F9 to view the MERGEFIELD codes.

You probably have

{ MERGEFIELD Apt }

at the moment.

Change it so you have

text and fields above { IF "{ MERGEFIELD Apt }" = "" "" "
{ MERGEFIELD Apt }" }
text and fields below

Where all the {} are the special field code braces that you can insert using
ctrl-F9

Do that in label 1, then re-propagate the label content (unless you're using
a Tablet PC, in which case it may not work and you can try one of the
methods at http://tips.pjmsn.me.uk/t0005.htm )

Peter Jamieson