Hey @ejodell,
Thanks for posting in the Community.
The error message is most probably due to the fact that your Duo subscription has not run out yet, judging by your wording. As soon as your account reverts to free after the Duo subscription has expired, you should be able to accept the invitation to the Family subscription.
If that is not the case, let us know and we'll think of something else.
Hope this clears things a bit,
Cheers!
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