Add brackets to specify what you are dereferencing.

If you were using strictures, you would've been alerted to the syntax error: 'Global symbol "$my_hash" requires explicit package name'

use strict;

my %my_hash = (
    k1 => "123",
    k2 => ["Bach", "Bachi"],
);

my @my_array = @{$my_hash{"k2"}};

print @my_array;
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