I am trying to print the following in report heading.

"Test Date < Than Today "

Error is displayed Field name "Than" does not exit.

It is searching <Than field name in the master file as Field Identification character is "<"

How do I avoid this error?

Either avoid the "less" symbol (spell it out),

or put it in a defined variable
LESS/A1='<';
and change
"... < than ..."
to
"... <LESS than ..."

or put the whole legend in a variable
LEGEND/A40=' ... ';
"<LEGEND"

Unless it's a necessary evil to use the '<' in the heading, why not 'LT' or spell it out.

I have had to face that one before and decided to go with the LT rather than fuss with variables.

Hope everyone is staying warm this winter.

Hi! from Japan.
try in the following way.

"Test Date < | Than Today "

or
LEFT/A1=HEXBYT(60,'A1');