Join group membership link - new members not enabled or activated

Hi, I use the join group membership link for my group plans to save my group admins time.

One of my new clients this week had their first member register themselves but they were not enabled or activated so were unable to use the website.
I've just tested their link with a dummy email and member details, and that entry is also showing as disabled and unactivated.

I'm not sure how many people use their join group links, I think most group admins add their members manually.  Is there something in the configuration or settings that I may have missed?

Thanks
Tracey