If you issue that command you get message
HCPLNM053E no%one not in CP directory
if you have the error messages set to ON (set emsg on).
If EMSG is however set to TEXT, then you don't get the message number. If EMSG is set OFF, then you don't get the message at all, only the return code 53.
And remember, CP return codes are equal to the digits in the message code, even for CP wait state codes, which means you can issue help HCPnnnnW to have an explanation of the code (provided your system is running again of course). This is only true for the CP return codes, not for CMS or other environments.
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