Mouse buttons 4 and 5 not registering as hotkeys (Android), basically mouse side buttons.

I play with my keyboard and mouse connected to phone via hub and everything works fine except.

• i select the hotkey I wanted to change and when I press the extra button in my gaming mouse it doesn't register the button or clicking it? But I want to use my extra gaming mouse buttons as hotkeys please fix this
• I am using Razer cobra wired mice everything is clear in the video
• minecraft pe android phone
  -game is latest version bought from play store