The cause of the problems is found, now let's look at some other things. Most often when you say "our $variable" you mean "my $variable".

"my $variable" means "please create a brand new variable with this name that's accessible only within this block". "our $variable" on the other hand means just "I'm going to use the global variable (OK, package variable, there are multiple namespaces for globals) with this name within this block. I know it's global, but I do not want to waste time typing out its whole name each time". "our $variable", doesn't create a new variable, it just silences use strict;.

Compare,

use strict;
{ my $x; $x = 1; print "\$x=$x\n"; }
{ my $x; $x +=1; print "\$x=$x\n"; }
# and
{ our $y; $y = 1; print "\$y=$y\n"; }
{ our $y; $y +=1; print "\$y=$y\n"; }
# and see the globals in the main namespace
print "\$main::x=$main::x, \$main::y=$main::y\n";
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