my %hashofstates; << This declares a hash : "%hashofstates" .

$hashofstates->($key) << This attempts to access a SCALAR REFERENCE : "$hashofstates" , a totally different animal that does not exist.

The distinction between the hash and the hash-ref is the use of the DEREFERENCING operator "->".

You probably wanted:

 $hashofstates{$key}
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Also note the use of Curly brackets (Not parens) to contain hash keys.