I have two solutions that could work in this case.
One solution is the family member(s) experiencing issues create new account and join the new Premium Family subscription. They (or you) can transfer the music and followers using the steps here so nothing get's lost.
The second one would be that you cancel your subscription, your sister reactivates hers and they all join that one again. I would also like to know what issues exactly you had experienced before and help them find a solution.
Keep me posted and let me know what you decide!
Billy-JRock Star 24
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