I made some experiment with these lines of codes and maybe I find an issue (I'm not a perl expert...). If input file is like below, with two START-END sections in succession, perl script seems to skip the "START" line after the previous "END" ones, and so it doesn't print the content of the paragraph. I can't say which can be the reason for this behaviour

__DATA__

XXXX
YYYY
START
These are the first
set of lines
which are to be extracted
END
START
New line
And new 
Will be extracted?
END
XXX
ZZZ
YYY
START
These are the second
set of lines
which are to be extracted
END
aasds
tteret
tertetr
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