Turning off your mobile data does not actually help you save data. It would only help you to not use the Internet.
Apps and Services you used on your phone are already programmed to run In a certain way. Even if you switch off your data, all the processes will still run anytime you switch on your data. Push Notifications and Messages will still come in Immediately to switch on your data.
To avoid this,
— Go to Settings
— Turn Off Background Data for the Apps
This will make them only use your data when you open the Apps
Watch The Video Tutorial Below For More Details 👇