Invite somebody which already has an account

Hello, I am Sebastien, and I just tested Kanboard.

I would like to invite somebody on my kanboard, so on “user management”, I clicked on “invite peoples”
this people well received email and clicked on link, but when he clicked on link to join its team, he has a form asking him to subcribe.
But he already has an account on Kanboard.

So when he fills every fields, he receive message “this username is already taken”

Is it possible to invite somebody which already has an account ?

Have a good day

Why would you invite someone that already has an account? The invite feature is to invite someone to create an account, if the person already has an account… ?