Per Form 172 instructions, a separate Form 172 should be prepared for each NOL. However, currently only one instance of Form 172 is supported.

Use the NOL Worksheet from prior years to complete and attach additional 172's.

See: 
Common questions about Net Operating Losses(NOLs), Form 172 and diagnostic ref 61199 in Lacerte
Common questions about Net Operating Losses(NOLs), Form 172 and diagnostic ref 61199 in ProConnect T... 

*****
See Hot topics for Lacerte here.