Since I find your code very difficult to understand, I really do not know what the exact problem is. But, since you are having difficulties, try re-coding, like:

use strict;
use warnings;

my %ext;
opendir H, './';
my @files = grep { -f } readdir H;
closedir H;
for (@files) {
    my ($e) = ($_ =~ m/([^.]+)$/);
    $ext{$e}++;
}

print "$_ - $ext{$_}\n" for keys %ext;
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