How do I remove a technician from the default technician list?

How do I remove a technician from the default technician list?

I have a few technicians who were originally set up in the default technician list.
However, we no longer want them on that list and want to remove them.
I've tried going into their profile and unchecking the Default Technician option and save but that didn't work.
Is there a way of doing it without having to delete the technician account and recreating it?
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