There was an issue where the screen was split into three parts in the VR environment.
The problem was with Post Magic.
Actually, this scene was created a while ago, and I must have forgotten to properly fix the settings error.
But it's resolved now.
Besides that, I made some adjustments to the lighting to better suit the VR environment.
I also repositioned the canvas buttons for VR convenience.
If you're not satisfied with the placement, you can adjust it using the plugin inside the atom (Empty Canvas) where the canvas plugin is applied.