Why doesn't the floating icon dissapear or appear unless I turn it OFF/ON from the settings?


This is a privacy "improvement" added to Android 10 that the developers have to comply with. With Android 10, apps can no longer launch activities in the background without user interaction.
These restrictions help minimize interruptions and keep you more in control of what's shown on their screen.
Apps will now need to seek permission from users to launch background activities by sending them a notification.