If the condition is false (numeric zero, undef, or the empty string for example), then the call won't be made.

The docs for pathrm() state "An optional second argument makes it call pathempty() before any rmdir()'s when set to true.", so you might want to check and make sure that argument is present and true.

See also $File::Copy::Recursive::RMTrgFil for more ifno on why things might not be what they seem.

Posting some code you've tried might help us help you. Reading some docs and code might help you help yourself.