My UAP client wants to register for UMP

Someone is an affiliate now for my website (they signed up on UAP on my website).

That same person now wants to buy my online course, but would need to register with UMP on my website to do that. They can’t do that because when they go to register it says the email is already in use. How can they remain an affiliate, but still register for UMP and purchase my course?

There is a button in UMP to become an affiliate, but not there’s no button in UAP to become a member of UMP.

Seems they were separated features. They may need to register an account with a new email address.