Quote
Note: Built-in identifiers of the same name have priority.


Quote from the "Custom Identifiers" section of the mirc.chm help file.

You have to rename the alias.

https://forums.mirc.com/ubbthreads....-warn-collision-w-new-identifier-command

https://forums.mirc.com/ubbthreads.php/topics/267312/min-max

https://forums.mirc.com/ubbthreads.php/topics/265240/need-code-help