it needs to be in the sub

sub store_items {
   my $dbh = shift;
   ....
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If this is the case then follow my previous suggestion and use Data::Dumper to print out the database handle right before your error and see what you get.

sub store_items {
   my $dbh = shift;
   use Data::Dumper;
   print Dumper $dbh;
   ...
[download]