Lines 50 and 51 are:

                $metrics{$product}{$date} = $day;
                $metrics{$product}{$date}{$hour}{$user} = $val;

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So, on line 50 you set $metrics{$product}{$date} to be a scalar and then on line 51 you try to treat it as a hash ref. That's incompatible.

In reply to Re^3: Why am I getting Can't use string (<string value>) as an ARRAY ref wile "strict refs" in use by hippo
in thread Why am I getting Can't use string (<string value>) as an ARRAY ref wile "strict refs" in use by 5NOMAD7

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