Bluetooth mouse does not work properly

You probably turned on inverted y or x. Go to the controls settings and switch it off. You have noted that you are playing on a phone, so using a mouse is probably not intended.

Yes,this is not a problem with one kind of mouse, but with all mice.This problem has not been solved in the high version.If you really want to use the keyboard and mouse to play, I suggest you change the platform.

And you're wrong. This isn't about settings. The mouse X and Y axes are completely crossed and inverted. Up moves view left, down moves right, right looks down, left looks up. Crucially, when "Invert Y-Axis" is ON, the error changes: moving left looks down, and moving right looks up. This proves it's a game-breaking input mapping bug in the code, not a user preference issue.

Of course, if you really want to play Minecraft Bedrock on phone with keyboard and mouse, you could try turning the mouse sideways — which, by the way, is exactly how I’m playing right now.