Username as Slug URL

Dear Username Changer Colleague,

Thank you for this excellent plugin. It was very helpful to change my username from my email to my first name: https://prnt.sc/vfruyr.

How do I ensure that this new username (https://prnt.sc/vfrwll) creates a new HTML slug rather than use my old username (https://prnt.sc/vfrwa8)?

Thanks,
Nate

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