Why can't I access lexical variables via typeglob?

I don't understand why the example below is given below (test 2). Why can't I access the bb variable from the * bb ball?

use Test::More tests => 4;

$aa = 1;
my $bb = 2;   # HERE!
local $cc = 3;
our $dd = 4;

is(${*aa}, 1, "$ \*aa should be 1");
is(${*bb}, 2, "$ \*bb (my) should be 2");
is(${*cc}, 3, "$ \*cc (local) should be 3");
is(${*dd}, 4, "$ \*dd (our) should be 4");

      

        
        
        
      

    

Output signal

1..4
ok 1 - *aa should be 1
#   Failed test '*bb (my) should be 2'
#   at untitled line 10.
#          got: undef
#     expected: '2'
# Looks like you failed 1 test of 4.
not ok 2 - *bb (my) should be 2
ok 3 - *cc (local) should be 3
ok 4 - *dd (our) should be 4

      

        
        
        
      

    

Under perl 5.16.0

thank