You don't want to loop on while (... each %hash) { and modify the hash inside of the loop. Try doing:

foreach my $key (keys %hash) {
   my $val = $hash{$key};
   ...
}
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instead. That way you are iterating over what were the items in the hash before you began iterating.

Oh, and you should really format posts before putting 'em up. Use the "Preview" button; it's your friend. Updated: thanks!