EFB screen unlocks then a moment later comes back to the lock screen.
There are two possible fixes for this issue that have been reported as working.
1) Switching the GPU rendering helps with reliability. This can be done by closing down MSFS, opening the fenix app, and changing GPU rendering.
2) The alternative method another user found was to re-install fenix completely. While we understand this is more of a nuclear option, it has proven to fix the issue for the user to the user's satisfaction.