I'm having a hard time understanding your question, but a few things look suspicious:

{ $tlvHash{pktClassList} = "@pktClassList" }
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Do you really want to inject spaces between array elements here? If not, get rid of the quotes.

Try to eliminate the switch/case statement for debugging purposes, as Switch has many unusual side-effects.

Show your data using Data::Dumper. That might clarify things:

use Data::Dumper;
print Dumper(\%tlvHash);
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