Environment error when using FTOUCH in hpux

I have NATURAL v. 5.1.1 I’m trying to run the ftouch utility but I’m receiving an environment error.

bccdev2:/pgwsag/bccqam11/sag/nat/v51113/bin> ./ftouch lib=QAM11 convert

FTOUCH UTILITY V 5.1.1 Pl 13 Software AG 2003

Not able to find “NATDIR” and/or “NATVERS” environment variable!

If you have set the “NATDIR” environment variable,
please check that it does not contain invalid or
whitespace characters!
“NATVERS” should only contain the NATURAL version

Did you check your NATDIR/NATVERS variables?

echo $NATDIR