Does it work if you drop the /g at the end of your regex?
Some food for thought: 
use strict;
use warnings;

my $string = 'foo bar';
if ($string =~ m{bar}g) {
    print "bar\n";
}
if ($string =~ m{foo}g) {
    print "foo\n";
}
if ($string =~ m{bar}g) {
    print "bar\n";
}

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output: 
bar
bar

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without the /g it will print: 
bar
foo
bar

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The /g will keep the current position in the string and as such you are later continuing your matching from that position. If you just want to match your entire string (as it seems in this case), simply try dropping the /g.
As tobyink said, it would be easier if you provided some input data.

Update:
A stackoverflow link which explains it: http://stackoverflow.com/questions/6969208/help-understanding-global-flag-in-perl

In reply to Re: regex problem: doesn't work on the first search but works on the second by rminner
in thread regex problem: doesn't work on the first search but works on the second by onlyauto

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