If you want to unregister a nickname, so that NickServ no longer protects it and considers it taken, then you should use the DROP command. When issuing that command, NickServ will immediately drop that nickname, along with all the customizations you have made to it.

Before using this command you must use the IDENTIFY command with the nickname password. Please note that after dropping a nickname, it becomes available for immediate registration by someone else, so exercise caution when using this command.

If after dropping a nickname, someone else registers it, you cannot reclaim that nickname back until the new owner lets it expire or drops it. The command is:

/NickServ drop Nickname
(Where 'Nickname' is the nick you want to drop.)

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