I’ve run into this a few times and it is frustrating so I’m sure others must be as well.
When trying to create a new Planner “Plan” in Microsoft Teams, you might be unable to getting the error “We couldn’t save your tab settings. Please try again”. You’ll also likely fine that if you go into Planner itself, you won’t be able to select this Team/Microsoft 365 Group as a place to create plans in.
And you might even be the owner of that Team (as I was).
I can’t tell you “why” this occurs because I didn’t architect the dang thing. But I CAN tell you what worked for me. 😎
The fix for me (and might work for you too) was simply to go into the Microsoft Teams Admin Center (assuming you have the rights to, if not, point this article to your Microsoft 365 Admin and ask them to try this…) and remove my account as the Team Owner, wait a few minutes and then re-add myself.
Boom! That did the trick. Hope it helps you. And if you are still reading and want to do more awesome things in Teams, maybe check out our tool “Navo” as it might also save you more time in your busy day as the “Directory for your Connected Workplace”.