@MojangSupport Bedrock on Switch has been signing out of my kids' microsoft account every single time they play the game for the past month. I have to run over to help them use the game EVERY. SINGLE. TIME.
We apologize for the inconvenience, but this is currently a known issue. The team is currently working on a fix that we hope to have out to everyone as soon as possible. Thank you for your patience while we work on the solution! ^CD