Issue with stream team owners and temporary suspension/ban
If someone owns a stream team and gets a temporary suspension or banned (which could happen with mass reporting, but that's a whole other issue) they get removed from their own stream team.
The two biggest issues here are that people don't get their teams back, and that twitch doesn't know about this issue so they don't know how to help anyone with this issue.
Give the original owners their teams after coming back and tell people how to fix the issue if they need help. The way you fix this very niche issue is just go to the settings where you add other people to the team, then add yourself back. It seems like a simple fix, but when you don't see your team anymore people will usually contact twitch first to see what happened.
I'm not a partnered streamer myself, but a buddy of mine went through this. She got a few non helpful responses from twitch then had to figure it out on her own. From his most recent ban, Vinesauce isn't even on his own stream team as of the time I'm posting this. Even if twitch knows how to respond properly in the future, people that don't know they're having the issue won't have it fixed unless twitch treats this like a bug to fix.