Family library - Can't create a world or connect on microsoft account on a secondary account

I just bought and installed Minecraft on an Android 10 tablet with a family library.
The game works fine on my main accout (parent) but I can't play or create a new world on the kid account.

• Minecraft bought and tested with the main account, everything is fine.
• Loggout from the main account
• Login on the "kid" account, can launch Minecraft fine (Family library)
• Error if I try to connect to a microsoft account :
  "Failed to login - We tried to sign you in to your Microsoft Account, but something went wrong"
• Error if I try to create a world :
  "There was a problem loading this world"

 Is there anything I can provide to help resolve this issue ?

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Upadte:

It's seem that I had to switch parameters from  external vs application storage to have an "authorization popup".
I gave the asked rights, I am now able to create a new world and play the game on the second account.