uniq works as I expect it to. It only prints out one "c", not two:

use strict;
use warnings;
use List::MoreUtils qw(uniq);

my @trnAccounts = qw(a b c c d);
my @unique_accounts = uniq(@trnAccounts);

foreach (@unique_accounts) {
#    print @unique_accounts, "\n";
    print $_, "\n";
}

__END__

a
b
c
d
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