Character decoding is the process of taking bytes and returning the characters they represent. That error indicates you asked the function to decode something that wasn't bytes. 
>perl -MEncode -we"decode('UTF-8', qq{\x{123}})"
Cannot decode string with wide characters at ...

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Why your input isn't what you think it is, I don't know. You did not provide any information that would help answer that question.

In reply to Re: Double Decoding Issue by ikegami
in thread Double Decoding Issue by siraj

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