The following works fine for me: 
$customer->[0]{_address1} = 'hello';
my $i = 1;
my $varname = '_address' . $i;
print $customer->[0]{$varname};

[download]
prints "hello". Perhaps your issue lies elsewhere. If you can come up with a small runnable program that illustrates this error that may be more helpful.

In reply to Re: Hash name variable substitution by Errto
in thread Hash name variable substitution by peterb

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