A dash “-” in @username causes link to profile page error

Hi, nice chat plugin, works great on my site.

I have the chat names set as “Link to page” to point at users’ profile pages using the template:

https://mysite.com/members/{username}/

All works fine, except if a username contains a dash “-“, then it results in a Page Not Found error.

eg. username @johnsmith = works fine.
but username @john-smith = causes Page Not Found.

Can you advise?
Thanks.

My site uses:

Wordpress 5.4.4
Twenty Sixteen theme
Buddypress 6.2.0