Duo partner not being allowed to join saying can only join once

[#1]

They’re getting this message You can join someone else's Premium plan only once every 12 months.
Still want to change plans? We'll help you find another Premium plan that's right for you

[Maxim]

Hey there,

Thanks for reaching out.

In that case, they've been part of at least two Premium Duo/Family plans in the past and have switched from one to another within the last 12 months. They'll, unfortunately, have to wait until those 12 months are up or they can create a new account if they'd like to join your plan.

I hope this clears things up 🙂